Buffer compositions

ABSTRACT

Buffer compositions comprising semiconductive oxide particles and at least one of (a) a fluorinated acid polymer and (b) a semiconductive polymer doped with a fluorinated acid polymer are provided. Semiconductive oxide particles include metal oxides and bimetallic oxides. Acid polymers are derived from monomers or comonomers of polyolefins, polyacrylates, polymethacrylates, polyimides, polyamides, polyaramids, polyacrylamides, polystyrenes. The polymer backbone, side chains, pendant groups or combinations thereof may be fluorinated or highly fluorinated. Semiconductive polymers include polymers or copolymers derived from thiophenes, pyrroles, anilines, and polycyclic heteroaromatics. Methods for preparing buffer compositions are also provided.

RELATED U.S. APPLICATIONS

This application claims priority to U.S. provisional application Ser.No. 60/694,794, filed Jun. 28, 2005.

BACKGROUND INFORMATION

1. Field of the Disclosure

This disclosure relates in general to high work function transparentconductors for use in electronic devices.

2. Description of the Related Art

Organic electronic devices define a category of products that include anactive layer. Such devices convert electrical energy into radiation,detect signals through electronic processes, convert radiation intoelectrical energy, or include one or more organic semiconductor layers.

Organic light-emitting diodes (OLEDs) are organic electronic devicescomprising an organic layer capable of electroluminescence. OLEDscontaining conducting polymers can have the following configuration:

anode/buffer layer/EL material/cathode

Additional, optional layers, materials or components may be incorporatedinto this general configuration. The anode is typically any materialthat has the ability to inject holes into the electroluminescent (“EL”)material, such as, for example, indium/tin oxide (ITO). The anode isoptionally supported on a glass or plastic substrate. The buffer layeris typically an electrically conducting polymer and facilitates theinjection of holes from the anode into the EL material layer. ELmaterials include fluorescent compounds, fluorescent and phosphorescentmetal complexes, conjugated polymers, and mixtures thereof. The cathodeis typically any material (such as, e.g., Ca or Ba) that has the abilityto inject electrons into the EL material. At least one of the anode orcathode is transparent or semi-transparent to allow for light emission.

ITO is frequently used as the transparent anode. However, the workfunction of ITO is relatively low, typically in the range of 4.6 eV.This results in less effective injection of holes into the EL material.In some cases, the work function of ITO can be improved by surfacetreatment. However, these treatments sometime result in products thatare not stable and further result in reduced device lifetime.

Accordingly, there is a need for compositions and layers preparedtherefrom to improve the properties of the device.

SUMMARY

There is provided a buffer composition comprising semiconductive oxideparticles and at least one of (a) a fluorinated acid polymer and (b) asemiconductive polymer doped with a fluorinated acid polymer.

In another embodiment, there is provided a buffer layer made from thenew buffer composition.

In another embodiment, there is provided an electronic device comprisingthe buffer layer.

The foregoing general description and the following detailed descriptionare exemplary and explanatory and are not restrictive of the invention,as defined in the specification and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is illustrated by way of example and not limitation in theaccompanying figures.

FIG. 1 is a diagram illustrating contact angle.

FIG. 2 is a schematic diagram of an organic electronic device.

Skilled artisans appreciate that objects in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the objects in the figures may bemagnified relative to other objects to help to improve understanding ofembodiments.

DETAILED DESCRIPTION

There is provided a buffer composition comprising semiconductive oxideparticles and at least one of (a) a fluorinated acid polymer and (b) asemiconductive polymer doped with a fluorinated acid polymer.

Many aspects and embodiments are described herein and are exemplary andnot limiting. After reading this specification, skilled artisans willappreciate that other aspects and embodiments are possible withoutdeparting from the scope of the invention.

As used herein, the term “semiconductive” refers to material havingelectrical conductivity greater than insulators but less than goodconductors. In one embodiment, a film of a semiconductive material has aconductivity of less than 0.1 S/cm and greater than 10⁻⁸ S/cm. The term“fluorinated acid polymer” refers to a polymer having acidic groups,where at least some of the hydrogens have been replaced by fluorine.Fluorination can occur on the polymer backbone, on side chains attachedto the backbone, in pendant groups, or in combinations of these. Theterm “acidic group” refers to a group capable of ionizing to donate ahydrogen ion to a base to form a salt. As used herein, the term“semiconductive polymer” refers to any polymer or oligomer which isinherently or intrinsically capable of electrical conductivity withoutthe addition of carbon black or conductive metal particles. The term“polymer” encompasses homopolymers and copolymers. The term “doped” isintended to mean that the semiconductive polymer has a polymericcounterion derived from a polymeric acid to balance the charge on theconductive polymer.

1. Semiconductive Oxide Particles

In one embodiment, semiconductive oxide materials comprise an oxide ofan element selected from group 2 through group 12 of the periodic table.In one embodiment, semiconductive oxide materials comprise an oxide ofan element selected from group 2 and group 12. Group numberscorresponding to columns within the periodic table of the elements usethe “New Notation” convention as seen in the CRC Handbook of Chemistryand Physics, 81^(st) Edition (2000), where the groups are numbered fromleft to right as 1-18.

In one embodiment, the inorganic semiconductive material is an inorganicoxide which may be a bimetallic oxide, such as Ni_(x)Co_(x-1)O_(3/4)(Science, p 1273-1276, vol 305, Aug. 27, 2004), indium-tin oxide(“ITO”), indium-zinc oxide (“IZO”), gallium-indium oxide, zinc-antimonydouble oxide and zirconium, or antimony doped oxide.

2. Semiconductive Polymer

Any semiconductive polymer can be used in the new composition. In oneembodiment, the semiconductive polymer will form a film which has aconductivity of at least 10⁻⁷ S/cm. The conductive polymers suitable forthe new composition can be homopolymers, or they can be copolymers oftwo or more respective monomers. The monomer from which the conductivepolymer is formed, is referred to as a “precursor monomer”. A copolymerwill have more than one precursor monomer.

In one embodiment, the semiconductive polymer is made from at least oneprecursor monomer selected from thiophenes, pyrroles, anilines, andpolycyclic aromatics. The polymers made from these monomers are referredto herein as polythiophenes, polypyrroles, polyanilines, and polycyclicaromatic polymers, respectively. The term “polycyclic aromatic” refersto compounds having more than one aromatic ring. The rings may be joinedby one or more bonds, or they may be fused together. The term “aromaticring” is intended to include heteroaromatic rings. A “polycyclicheteroaromatic” compound has at least one heteroaromatic ring.

In one embodiment, thiophene monomers contemplated for use to form thesemiconductive polymer comprise Formula I below:

wherein:

-   -   R¹ is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, alkoxy, alkanoyl, alkythio, aryloxy, alkylthioalkyl,        alkylaryl, arylalkyl, amino, alkylamino, dialkylamino, aryl,        alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,        arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid,        phosphoric acid, phosphonic acid, halogen, nitro, cyano,        hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, ether carboxylate, amidosulfonate, ether sulfonate, ester        sulfonate, and urethane; or both R¹ groups together may form an        alkylene or alkenylene chain completing a 3, 4, 5, 6, or        7-membered aromatic or alicyclic ring, which ring may optionally        include one or more divalent nitrogen, sulfur or oxygen atoms.

As used herein, the term “alkyl” refers to a group derived from analiphatic hydrocarbon and includes linear, branched and cyclic groupswhich may be unsubstituted or substituted. The term “heteroalkyl” isintended to mean an alkyl group, wherein one or more of the carbon atomswithin the alkyl group has been replaced by another atom, such asnitrogen, oxygen, sulfur, and the like. The term “alkylene” refers to analkyl group having two points of attachment.

As used herein, the term “alkenyl” refers to a group derived from analiphatic hydrocarbon having at least one carbon-carbon double bond, andincludes linear, branched and cyclic groups which may be unsubstitutedor substituted. The term “heteroalkenyl” is intended to mean an alkenylgroup, wherein one or more of the carbon atoms within the alkenyl grouphas been replaced by another atom, such as nitrogen, oxygen, sulfur, andthe like. The term “alkenylene” refers to an alkenyl group having twopoints of attachment.

As used herein, the following terms for substituent groups refer to theformulae given below: “alcohol” —R³—OH “amido” —R³—C(O)N(R⁶) R⁶“amidosulfonate” —R³—C(O)N(R⁶) R⁴—SO₃Z “benzyl” —CH₂—C₆H₅ “carboxylate”—R³—C(O)O—Z or —R³—O—C(O)—Z “ether” —R³—(O—R⁵)_(p)—O—R⁵ “ethercarboxylate” —R³—O—R⁴—C(O)O—Z or —R³—O—R⁴—O—C(O)—Z “ether sulfonate”—R³—O—R⁴—SO₃Z “ester sulfonate” —R³—O—C(O)—R⁴—SO₃Z “sulfonimide”—R³—SO₂—NH—SO₂—R⁵ “urethane” —R³—O—C(O)—N(R⁶)₂

-   -   where all “R” groups are the same or different at each        occurrence and:        -   R³ is a single bond or an alkylene group        -   R⁴ is an alkylene group        -   R⁵ is an alkyl group        -   R⁶ is hydrogen or an alkyl group        -   p is 0 or an integer from 1 to 20        -   Z is H, alkali metal, alkaline earth metal, N(R⁵)₄ or R⁵            Any of the above groups may further be unsubstituted or            substituted, and any group may have F substituted for one or            more hydrogens, including perfluorinated groups. In one            embodiment, the alkyl and alkylene groups have from 1-20            carbon atoms.

In one embodiment, in the thiophene monomer, both R¹ together form—O—(CHY)_(m)—O—, where m is 2 or 3, and Y is the same or different ateach occurrence and is selected from hydrogen, halogen, alkyl, alcohol,amidosulfonate, benzyl, carboxylate, ether, ether carboxylate, ethersulfonate, ester sulfonate, and urethane, where the Y groups may bepartially or fully fluorinated. In one embodiment, all Y are hydrogen.In one embodiment, the polythiophene ispoly(3,4-ethylenedioxythiophene). In one embodiment, at least one Ygroup is not hydrogen. In one embodiment, at least one Y group is asubstituent having F substituted for at least one hydrogen. In oneembodiment, at least one Y group is perfluorinated.

In one embodiment, the thiophene monomer has Formula I(a):

wherein:

-   -   R⁷ is the same or different at each occurrence and is selected        from hydrogen, alkyl, heteroalkyl, alkenyl, heteroalkenyl,        alcohol, amidosulfonate, benzyl, carboxylate, ether, ether        carboxylate, ether sulfonate, ester sulfonate, and urethane,        with the proviso that at least one R⁷ is not hydrogen, and    -   m is 2 or 3.

In one embodiment of Formula I(a), m is two, one R⁷ is an alkyl group ofmore than 5 carbon atoms, and all other R⁷ are hydrogen. In oneembodiment of Formula I(a), at least one R⁷ group is fluorinated. In oneembodiment, at least one R⁷ group has at least one fluorine substituent.In one embodiment, the R⁷ group is fully fluorinated.

In one embodiment of Formula I(a), the R⁷ substituents on the fusedalicyclic ring on the thiophene offer improved solubility of themonomers in water and facilitate polymerization in the presence of thefluorinated acid polymer.

In one embodiment of Formula I(a), m is 2, one R⁷ is sulfonicacid-propylene-ether-methylene and all other R⁷ are hydrogen. In oneembodiment, m is 2, one R⁷ is propyl-ether-ethylene and all other R⁷ arehydrogen. In one embodiment, m is 2, one R⁷ is methoxy and all other R⁷are hydrogen. In one embodiment, one R⁷ is sulfonic aciddifluoromethylene ester methylene (—CH₂—O—C(O)—CF₂—SO₃H), and all otherR⁷ are hydrogen.

In one embodiment, pyrrole monomers contemplated for use to form thesemiconductive polymer comprise Formula II below.

where in Formula II:

-   -   R¹ is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, alkoxy, alkanoyl, alkythio, aryloxy, alkylthioalkyl,        alkylaryl, arylalkyl, amino, alkylamino, dialkylamino, aryl,        alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,        arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid,        phosphoric acid, phosphonic acid, halogen, nitro, cyano,        hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, amidosulfonate, ether carboxylate, ether sulfonate, ester        sulfonate, and urethane; or both R¹ groups together may form an        alkylene or alkenylene chain completing a 3, 4, 5, 6, or        7-membered aromatic or alicyclic ring, which ring may optionally        include one or more divalent nitrogen, sulfur or oxygen atoms;        and    -   R² is independently selected so as to be the same or different        at each occurrence and is selected from hydrogen, alkyl,        alkenyl, aryl, alkanoyl, alkylthioalkyl, alkylaryl, arylalkyl,        amino, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,        ether, ether carboxylate, ether sulfonate, ester sulfonate, and        urethane.

In one embodiment, R¹ is the same or different at each occurrence and isindependently selected from hydrogen, alkyl, alkenyl, alkoxy,cycloalkyl, cycloalkenyl, alcohol, benzyl, carboxylate, ether,amidosulfonate, ether carboxylate, ether sulfonate, ester sulfonate,urethane, epoxy, silane, siloxane, and alkyl substituted with one ormore of sulfonic acid, carboxylic acid, acrylic acid, phosphoric acid,phosphonic acid, halogen, nitro, cyano, hydroxyl, epoxy, silane, orsiloxane moieties.

In one embodiment, R² is selected from hydrogen, alkyl, and alkylsubstituted with one or more of sulfonic acid, carboxylic acid, acrylicacid, phosphoric acid, phosphonic acid, halogen, cyano, hydroxyl, epoxy,silane, or siloxane moieties.

In one embodiment, the pyrrole monomer is unsubstituted and both R¹ andR² are hydrogen.

In one embodiment, both R¹ together form a 6- or 7-membered alicyclicring, which is further substituted with a group selected from alkyl,heteroalkyl, alcohol, benzyl, carboxylate, ether, ether carboxylate,ether sulfonate, ester sulfonate, and urethane. These groups can improvethe solubility of the monomer and the resulting polymer. In oneembodiment, both R¹ together form a 6- or 7-membered alicyclic ring,which is further substituted with an alkyl group. In one embodiment,both R¹ together form a 6- or 7-membered alicyclic ring, which isfurther substituted with an alkyl group having at least 1 carbon atom.

In one embodiment, both R¹ together form —O—(CHY)_(m)—O—, where m is 2or 3, and Y is the same or different at each occurrence and is selectedfrom hydrogen, alkyl, alcohol, benzyl, carboxylate, amidosulfonate,ether, ether carboxylate, ether sulfonate, ester sulfonate, andurethane. In one embodiment, at least one Y group is not hydrogen. Inone embodiment, at least one Y group is a substituent having Fsubstituted for at least one hydrogen. In one embodiment, at least one Ygroup is perfluorinated.

In one embodiment, aniline monomers contemplated for use to form thesemiconductive polymer comprise Formula III below.

wherein:

a is 0 or an integer from 1 to 4;

b is an integer from 1 to 5, with the proviso that a+b=5; and

R¹ is independently selected so as to be the same or different at eachoccurrence and is selected from hydrogen, alkyl, alkenyl, alkoxy,alkanoyl, alkythio, aryloxy, alkylthioalkyl, alkylaryl, arylalkyl,amino, alkylamino, dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl,alkylsulfonyl, arylthio, arylsulfinyl, alkoxycarbonyl, arylsulfonyl,acrylic acid, phosphoric acid, phosphonic acid, halogen, nitro, cyano,hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate, ether,ether carboxylate, amidosulfonate, ether sulfonate, ester sulfonate, andurethane; or both R¹ groups together may form an alkylene or alkenylenechain completing a 3, 4, 5, 6, or 7-membered aromatic or alicyclic ring,which ring may optionally include one or more divalent nitrogen, sulfuror oxygen atoms.

When polymerized, the aniline monomeric unit can have Formula IV(a) orFormula IV(b) shown below, or a combination of both formulae.

where a, b and R¹ are as defined above.

In one embodiment, the aniline monomer is unsubstituted and a=0.

In one embodiment, a is not 0 and at least one R¹ is fluorinated. In oneembodiment, at least one R¹ is perfluorinated.

In one embodiment, fused polycylic heteroaromatic monomers contemplatedfor use to form the semiconductive polymer have two or more fusedaromatic rings, at least one of which is heteroaromatic. In oneembodiment, the fused polycyclic heteroaromatic monomer has Formula V:

wherein:

-   -   Q is S, Se, Te, or NR⁶;    -   R⁶ is hydrogen or alkyl;    -   R⁸, R⁹, R¹⁰, and R¹¹ are independently selected so as to be the        same or different at each occurrence and are selected from        hydrogen, alkyl, alkenyl, alkoxy, alkanoyl, alkythio, aryloxy,        alkylthioalkyl, alkylaryl, arylalkyl, amino, alkylamino,        dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl, alkylsulfonyl,        arylthio, arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic        acid, phosphoric acid, phosphonic acid, halogen, nitro, nitrile,        cyano, hydroxyl, epoxy, silane, siloxane, alcohol, benzyl,        carboxylate, ether, ether carboxylate, amidosulfonate, ether        sulfonate, ester sulfonate, and urethane; and    -   at least one of R⁸ and R⁹, R⁹ and R¹⁰, and R¹⁰ and R¹¹ together        form an alkenylene chain completing a 5 or 6-membered aromatic        ring, which ring may optionally include one or more divalent        nitrogen, sulfur or oxygen atoms.

In one embodiment, the fused polycyclic heteroaromatic monomer hasFormula V(a), V(b), V(c), V(d), V(e), V(f), and V(g):

wherein:

-   -   Q is S, Se, Te, or NH; and    -   T is the same or different at each occurrence and is selected        from S, NR⁶, O, SiR⁶ ₂, Se, Te, and PR⁶;    -   R⁶ is hydrogen or alkyl.

The fused polycyclic heteroaromatic monomers may be substituted withgroups selected from alkyl, heteroalkyl, alcohol, benzyl, carboxylate,ether, ether carboxylate, ether sulfonate, ester sulfonate, andurethane. In one embodiment, the substituent groups are fluorinated. Inone embodiment, the substituent groups are fully fluorinated.

In one embodiment, the fused polycyclic heteroaromatic monomer is athieno(thiophene). Such compounds have been discussed in, for example,Macromolecules, 34, 5746-5747 (2001); and Macromolecules, 35, 7281-7286(2002). In one embodiment, the thieno(thiophene) is selected fromthieno(2,3-b)thiophene, thieno(3,2-b)thiophene, andthieno(3,4-b)thiophene. In one embodiment, the thieno(thiophene) monomeris substituted with at least one group selected from alkyl, heteroalkyl,alcohol, benzyl, carboxylate, ether, ether carboxylate, ether sulfonate,ester sulfonate, and urethane. In one embodiment, the substituent groupsare fluorinated. In one embodiment, the substituent groups are fullyfluorinated.

In one embodiment, polycyclic heteroaromatic monomers contemplated foruse to form the copolymer in the new composition comprise Formula VI:

wherein:

Q is S, Se, Te, or NR⁶;

T is selected from S, NR⁶, O, SiR⁶ ₂, Se, Te, and PR⁶;

E is selected from alkenylene, arylene, and heteroarylene;

R⁶ is hydrogen or alkyl;

-   -   R¹² is the same or different at each occurrence and is selected        from hydrogen, alkyl, alkenyl, alkoxy, alkanoyl, alkythio,        aryloxy, alkylthioalkyl, alkylaryl, arylalkyl, amino,        alkylamino, dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl,        alkylsulfonyl, arylthio, arylsulfinyl, alkoxycarbonyl,        arylsulfonyl, acrylic acid, phosphoric acid, phosphonic acid,        halogen, nitro, nitrile, cyano, hydroxyl, epoxy, silane,        siloxane, alcohol, benzyl, carboxylate, ether, ether        carboxylate, amidosulfonate, ether sulfonate, ester sulfonate,        and urethane; or both R¹² groups together may form an alkylene        or alkenylene chain completing a 3, 4, 5, 6, or 7-membered        aromatic or alicyclic ring, which ring may optionally include        one or more divalent nitrogen, sulfur or oxygen atoms.

In one embodiment, the semiconductive polymer is a copolymer of a firstprecursor monomer and at least one second precursor monomer. Any type ofsecond monomer can be used, so long as it does not detrimentally affectthe desired properties of the copolymer. In one embodiment, the secondmonomer comprises no more than 50% of the copolymer, based on the totalnumber of monomer units. In one embodiment, the second monomer comprisesno more than 30%, based on the total number of monomer units. In oneembodiment, the second monomer comprises no more than 10%, based on thetotal number of monomer units.

Exemplary types of second precursor monomers include, but are notlimited to, alkenyl, alkynyl, arylene, and heteroarylene. Examples ofsecond monomers include, but are not limited to, fluorene, oxadiazole,thiadiazole, benzothiadiazole, phenylenevinylene, phenyleneethynylene,pyridine, diazines, and triazines, all of which may be furthersubstituted.

In one embodiment, the copolymers are made by first forming anintermediate precursor monomer having the structure A-B-C, where A and Crepresent first precursor monomers, which can be the same or different,and B represents a second precursor monomer. The A-B-C intermediateprecursor monomer can be prepared using standard synthetic organictechniques, such as Yamamoto, Stille, Grignard metathesis, Suzuki, andNegishi couplings. The copolymer is then formed by oxidativepolymerization of the intermediate precursor monomer alone, or with oneor more additional precursor monomers.

In one embodiment, the semiconductive polymer is a copolymer of two ormore precursor monomers. In one embodiment, the precursor monomers areselected from a thiophene, a pyrrole, an aniline, and a polycyclicaromatic.

3. Fluorinated Acid Polymer

The fluorinated acid polymer (hereinafter referred to as “FAP”) can beany polymer which is fluorinated and has acidic groups. As used herein,the term “fluorinated” means that at least one hydrogen bonded to acarbon has been replaced with a fluorine. The term includes partiallyand fully fluorinated materials. In one embodiment, the fluorinated acidpolymer is highly fluorinated. The term “highly fluorinated” means thatat least 50% of the avialable hydrogens bonded to a carbon, have beenreplaced with fluorine. The term “acidic group” refers to a groupcapable of ionizing to donate a hydrogen ion to a Brønsted base to forma salt. The acidic groups supply an ionizable proton. In one embodiment,the acidic group has a pKa of less than 3. In one embodiment, the acidicgroup has a pKa of less than 0. In one embodiment, the acidic group hasa pKa of less than −5. The acidic group can be attached directly to thepolymer backbone, or it can be attached to side chains on the polymerbackbone or pendant groups. Examples of acidic groups include, but arenot limited to, carboxylic acid groups, sulfonic acid groups,sulfonimide groups, phosphoric acid groups, phosphonic acid groups, andcombinations thereof. The acidic groups can all be the same, or thepolymer may have more than one type of acidic group.

In one embodiment, the FAP is organic solvent wettable (“wettable FAP”).The term “organic solvent wettable” refers to a material which, whenformed into a film, is wettable by organic solvents. The term alsoincludes polymeric acids which are not film-forming alone, but whichwhen doped into a semiconductive polymer will form a film which iswettable. In one embodiment, the organic solvent wettable material formsa film which is wettable by phenylhexane with a contact angle less than40°.

In one embodiment, the FAP is organic solvent non-wettable(“non-wettable FAP”). The term “organic solvent non-wettable” refers toa material which, when formed into a film, is not wettable by organicsolvents. The term also includes polymeric acids which are notfilm-forming alone, but which when doped into a semiconductive polymerwill form a film which is non-wettable. In one embodiment, the organicsolvent non-wettable material forms a film on which phenylhexane has acontact angle greater than 40°.

As used herein, the term “contact angle” is intended to mean the angle φshown in FIG. 1. For a droplet of liquid medium, angle φ is defined bythe intersection of the plane of the surface and a line from the outeredge of the droplet to the surface. Furthermore, angle φ is measuredafter the droplet has reached an equilibrium position on the surfaceafter being applied, i.e., “static contact angle”. The film of theorganic solvent wettable fluorinated polymeric acid is represented asthe surface. In one embodiment, the contact angle is no greater than35°. In one embodiment, the contact angle is no greater than 30°. Themethods for measuring contact angles are well known.

In one embodiment, the FAP is water-soluble. In one embodiment, the FAPis dispersible in water. In one embodiment, the FAP forms a colloidaldispersion in water.

In one embodiment, the polymer backbone is fluorinated. Examples ofsuitable polymeric backbones include, but are not limited to,polyolefins, polyacrylates, polymethacrylates, polyimides, polyamides,polyaramids, polyacrylamides, polystyrenes, and copolymers thereof. Inone embodiment, the polymer backbone is highly fluorinated. In oneembodiment, the polymer backbone is fully fluorinated.

In one embodiment, the acidic groups are selected from sulfonic acidgroups and sulfonimide groups. In one embodiment, the acidic groups areon a fluorinated side chain. In one embodiment, the fluorinated sidechains are selected from alkyl groups, alkoxy groups, amido groups,ether groups, and combinations thereof.

In one embodiment, the wettable FAP has a fluorinated olefin backbone,with pendant fluorinated ether sulfonate, fluorinated ester sulfonate,or fluorinated ether sulfonimide groups. In one embodiment, the polymeris a copolymer of 1,1-difluoroethylene and2-(1,1-difluoro-2-(trifluoromethyl)allyloxy)-1,1,2,2-tetrafluoroethanesulfonicacid. In one embodiment, the polymer is a copolymer of ethylene and2-(2-(1,2,2-trifluorovinyloxy)-1,1,2,3,3,3-hexafluoropropoxy)-1,1,2,2-tetrafluoroethanesulfonicacid. These copolymers can be made as the corresponding sulfonylfluoride polymer and then can be converted to the sulfonic acid form.

In one embodiment, the wettable FAP is homopolymer or copolymer of afluorinated and partially sulfonated poly(arylene ether sulfone). Thecopolymer can be a block copolymer. Examples of comonomers include, butare not limited to butadiene, butylene, isobutylene, styrene, andcombinations thereof.

In one embodiment, the wettable FAP is a homopolymer or copolymer ofmonomers having Formula VII:

where:

b is an integer from 1 to 5,

R¹³ is OH or NHR¹⁴, and

R¹⁴ is alkyl, fluoroalkyl, sulfonylalkyl, or sulfonylfluoroalkyl.

In one embodiment, the monomer is “SFS” or SFSI” shown below:

After polymerization, the polymer can be converted to the acid form.

In one embodiment, the wettable FAP is a homopolymer or copolymer of atrifluorostyrene having acidic groups. In one embodiment, thetrifluorostyrene monomer has Formula VIII:

where:

-   -   W is selected from (CF₂)_(q), O(CF₂)_(q), S(CF₂)_(q),        (CF₂)_(q)O(CF₂)_(r), and SO₂(CF₂)_(q),    -   b is independently an integer from 1 to 5,    -   R¹³ is OH or NHR¹⁴, and    -   R¹⁴ is alkyl, fluoroalkyl, sulfonylalkyl, or        sulfonylfluoroalkyl.        In one embodiment, the monomer containing W equal to S(CF₂)_(q)        is polymerized then oxidized to give the polymer containing W        equal to SO₂(CF₂)_(q). In one embodiment, the polymer containing        R¹³ equal to F is converted its acid form where R¹³ is equal to        OH or NHR¹⁴.

In one embodiment, the wettable FAP is a sulfonimide polymer havingFormula IX:

where:

-   -   R_(f) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, or fluorinated        heteroarylene;    -   R_(g) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, fluorinated heteroarylene,        arylene, or heteroarylene; and    -   n is at least 4.

In one embodiment of Formula IX, R_(f) and R_(g) are perfluoroalkylenegroups. In one embodiment, R_(f) and R_(g) are perfluorobutylene groups.In one embodiment, R_(f) and R_(g) contain ether oxygens. In oneembodiment, n is greater than 20.

In one embodiment, the wettable FAP comprises a fluorinated polymerbackbone including a side chain having Formula X:

where:

-   -   R_(g) is selected from fluorinated alkylene, fluorinated        heteroalkylene, fluorinated arylene, fluorinated heteroarylene,        arylene, or heteroarylene;    -   R¹⁵ is a fluorinated alkylene group or a fluorinated        heteroalkylene group;    -   R¹⁶ is a fluorinated alkyl or a fluorinated aryl group; and    -   p is 0 or an integer from 1 to 4.

In one embodiment, the wettable FAP has Formula XI:

where:

-   -   R¹⁶ is a fluorinated alkyl or a fluorinated aryl group;    -   a, b, c, d, and e are each independently 0 or an integer from 1        to 4; and    -   n is at least 4.

The synthesis of these fluorinated acid polymers has been described in,for example, A. Feiring et al., J. Fluorine Chemistry 2000, 105,129-135; A. Feiring et al., Macromolecules 2000, 33, 9262-9271; D. D.Desmarteau, J. Fluorine Chem. 1995, 72, 203-208; A. J. Appleby et al.,J. Electrochem. Soc. 1993, 140(1), 109-111; and Desmarteau, U.S. Pat.No. 5,463,005.

In one embodiment, the wettable FAP comprises at least one repeat unitderived from an ethylenically unsaturated compound having Formula XII:

-   -   wherein d is 0, 1, or 2;    -   R¹⁷ to R²⁰ are independently H, halogen, alkyl or alkoxy of 1 to        10 carbon atoms, Y, C(R_(f)′)(R_(f)′)OR²¹, R⁴Y or OR⁴Y;    -   Y is COE², SO₂ E², or sulfonimide;    -   R²¹ is hydrogen or an acid-labile protecting group;    -   R_(f)′ is the same or different at each occurrence and is a        fluoroalkyl group of 1 to 10 carbon atoms, or taken together are        (CF₂)_(e) where e is 2 to 10;    -   R⁴ is an alkylene group;    -   E² is OH, halogen, or OR⁷; and    -   R⁵ is an alkyl group;

with the proviso that at least one of R¹⁷ to R²⁰ is Y, R⁴Y or OR⁴Y. R⁴,R⁵, and R¹⁷ to R²⁰ may optionally be substituted by halogen or etheroxygen.

Some illustrative, but nonlimiting, examples of representative monomersof Formula XII are presented below:

wherein R²¹ is a group capable of forming or rearranging to a tertiarycation, more typically an alkyl group of 1 to 20 carbon atoms, and mosttypically t-butyl.

Compounds of Formula XII wherein d=0, (e.g., Formula XII-a), may beprepared by cycloaddition reaction of unsaturated compounds of structure(XIII) with quadricyclane (tetracyclo[2.2.1.0^(2,6)0^(3,5)]heptane) asshown in the equation below.

The reaction may be conducted at temperatures ranging from about 0° C.to about 200° C., more typically from about 30° C. to about 150° C. inthe absence or presence of an inert solvent such as diethyl ether. Forreactions conducted at or above the boiling point of one or more of thereagents or solvent, a closed reactor is typically used to avoid loss ofvolatile components. Compounds of Formula XII with higher values of d(i.e., d=1 or 2) may be prepared by reaction of compounds of structure(XII) with d=0 with cyclopentadiene, as is known in the art.

In one embodiment, the wettable FAP is a copolymer which also comprisesa repeat unit derived from at least one fluoroolefin, which is anethylenically unsaturated compound containing at least one fluorine atomattached to an ethylenically unsaturated carbon. The fluoroolefincomprises 2 to 20 carbon atoms. Representative fluoroolefins include,but are not limited to, tetrafluoroethylene, hexafluoropropylene,chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride,perfluoro-(2,2-dimethyl-1,3-dioxole),perfluoro-(2-methylene-4-methyl-1,3-dioxolane), CF₂═CFO(CF₂)_(t)CF═CF₂,where t is 1 or 2, and R_(f)″OCF═CF₂ wherein R_(f)″ is a saturatedfluoroalkyl group of from 1 to about ten carbon atoms. In oneembodiment, the comonomer is tetrafluoroethylene.

In one embodiment, the non-wettable FAP comprises a polymeric backbonehaving pendant groups comprising siloxane sulfonic acid. In oneembodiment, the siloxane pendant groups have the formula below:—O_(a)Si(OH)_(b-a)R²² _(3-b)R²³R_(f)SO₃H

wherein:

a is from 1 to b;

b is from 1 to 3;

R²² is a non-hydrolyzable group independently selected from the groupconsisting of alkyl, aryl, and arylalkyl;

R²³ is a bidentate alkylene radical, which may be substituted by one ormore ether oxygen atoms, with the proviso that R²³ has at least twocarbon atoms linearly disposed between Si and R_(f); and

R_(f) is a perfluoralkylene radical, which may be substituted by one ormore ether oxygen atoms.

In one embodiment, the non-wettable FAP having pendant siloxane groupshas a fluorinated backbone. In one embodiment, the backbone isperfluorinated.

In one embodiment, the non-wettable FAP has a fluorinated backbone andpendant groups represented by the Formula (XIV)—O_(g)—[CF(R_(f) ²)CF—O_(h)]_(i)—CF₂CF₂SO₃H  (XIV)

wherein R_(f) ² is F or a perfluoroalkyl radical having 1-10 carbonatoms either unsubstituted or substituted by one or more ether oxygenatoms, h=0 or 1, i=0 to 3, and g=0 or 1.

In one embodiment, the non-wettable FAP has formula (XV)

where j≧0, k≧0 and 4≦(j+k)≦199, Q¹ and Q² are F or H, R_(f) ² is F or aperfluoroalkyl radical having 1-10 carbon atoms either unsubstituted orsubstituted by one or more ether oxygen atoms, h=0 or 1, i=0 to 3, g=0or 1, and E⁴ is H or an alkali metal. In one embodiment R_(f) ² is —CF₃,g=1, h=1, and i=1. In one embodiment the pendant group is present at aconcentration of 3-10 mol-%.

In one embodiment, Q¹ is H, k≧0, and Q² is F, which may be synthesizedaccording to the teachings of Connolly et al., U.S. Pat. No. 3,282,875.In another preferred embodiment, Q¹ is H, Q² is H, g=0, R_(f) ² is F,h=1, and i-1, which may be synthesized according to the teachings ofco-pending application Ser. No. 60/105,662. Still other embodiments maybe synthesized according to the various teachings in Drysdale et al., WO9831716(A1), and co-pending US applications Choi et al, WO 99/52954(A1),and 60/176,881.

In one embodiment, the non-wettable FAP is a colloid-forming polymericacid. As used herein, the term “colloid-forming” refers to materialswhich are insoluble in water, and form colloids when dispersed into anaqueous medium. The colloid-forming polymeric acids typically have amolecular weight in the range of about 10,000 to about 4,000,000. In oneembodiment, the polymeric acids have a molecular weight of about 100,000to about 2,000,000. Colloid particle size typically ranges from 2nanometers (nm) to about 140 nm. In one embodiment, the colloids have aparticle size of 2 nm to about 30 nm. Any colloid-forming polymericmaterial having acidic protons can be used. In one embodiment, thecolloid-forming fluorinated polymeric acid has acidic groups selectedfrom carboxylic groups, sulfonic acid groups, and sulfonimide groups. Inone embodiment, the colloid-forming fluorinated polymeric acid is apolymeric sulfonic acid. In one embodiment, the colloid-formingpolymeric sulfonic acid is perfluorinated. In one embodiment, thecolloid-forming polymeric sulfonic acid is a perfluoroalkylenesulfonicacid.

In one embodiment, the non-wettable colloid-forming FAP. is ahighly-fluorinated sulfonic acid polymer (“FSA polymer”). “Highlyfluorinated” means that at least about 50% of the total number ofhalogen and hydrogen atoms in the polymer are fluorine atoms, an in oneembodiment at least about 75%, and in another embodiment at least about90%. In one embodiment, the polymer is perfluorinated. The term“sulfonate functional group” refers to either to sulfonic acid groups orsalts of sulfonic acid groups, and in one embodiment alkali metal orammonium salts. The functional group is represented by the formula—SO₃E⁵ where E⁵ is a cation, also known as a “counterion”. E⁵ may be H,Li, Na, K or N(R₁)(R₂)(R₃)(R₄), and R₁, R₂, R₃, and R₄ are the same ordifferent and are and in one embodiment H, CH₃ or C₂H₅. In anotherembodiment, E⁵ is H, in which case the polymer is said to be in the“acid form”. E⁵ may also be multivalent, as represented by such ions asCa⁺⁺, and Al⁺⁺⁺. It is clear to the skilled artisan that in the case ofmultivalent counterions, represented generally as M^(x+), the number ofsulfonate functional groups per counterion will be equal to the valence“x”.

In one embodiment, the FSA polymer comprises a polymer backbone withrecurring side chains attached to the backbone, the side chains carryingcation exchange groups. Polymers include homopolymers or copolymers oftwo or more monomers. Copolymers are typically formed from anonfunctional monomer and a second monomer carrying the cation exchangegroup or its precursor, e.g., a sulfonyl fluoride group (—SO₂F), whichcan be subsequently hydrolyzed to a sulfonate functional group. Forexample, copolymers of a first fluorinated vinyl monomer together with asecond fluorinated vinyl monomer having a sulfonyl fluoride group(—SO₂F) can be used. Possible first monomers include tetrafluoroethylene(TFE), hexafluoropropylene, vinyl fluoride, vinylidine fluoride,trifluoroethylene, chlorotrifluoroethylene, perfluoro(alkyl vinylether), and combinations thereof. TFE is a preferred first monomer.

In other embodiments, possible second monomers include fluorinated vinylethers with sulfonate functional groups or precursor groups which canprovide the desired side chain in the polymer. Additional monomers,including ethylene, propylene, and R—CH═CH₂ where R is a perfluorinatedalkyl group of 1 to 10 carbon atoms, can be incorporated into thesepolymers if desired. The polymers may be of the type referred to hereinas random copolymers, that is, copolymers made by polymerization inwhich the relative concentrations of the comonomers are kept as constantas possible, so that the distribution of the monomer units along thepolymer chain is in accordance with their relative concentrations andrelative reactivities. Less random copolymers, made by varying relativeconcentrations of monomers in the course of the polymerization, may alsobe used. Polymers of the type called block copolymers, such as thatdisclosed in European Patent Application No. 1 026 152 A1, may also beused.

In one embodiment, FSA polymers for use in the present invention includea highly fluorinated, and in one embodiment perfluorinated, carbonbackbone and side chains represented by the formula—(O—CF₂CFR_(f) ³)_(a)—O—CF₂CFR_(f) ⁴SO₃E⁵wherein R_(f) ³ and R_(f) ⁴ are independently selected from F, Cl or aperfluorinated alkyl group having 1 to 10 carbon atoms, a=0, 1 or 2, andE⁵ is H, Li, Na, K or N(R1)(R2)(R3)(R4) and R1, R2, R3, and R4 are thesame or different and are and in one embodiment H, CH₃ or C₂H₅. Inanother embodiment E⁵ is H. As stated above, E⁵ may also be multivalent.

In one embodiment, the FSA polymers include, for example, polymersdisclosed in U.S. Pat. No. 3,282,875 and in U.S. Pat. Nos. 4,358,545 and4,940,525. An example of preferred FSA polymer comprises aperfluorocarbon backbone and the side chain represented by the formula—O—CF₂CF(CF₃)—O—CF₂CF₂SO₃E⁵where X is as defined above. FSA polymers of this type are disclosed inU.S. Pat. No. 3,282,875 and can be made by copolymerization oftetrafluoroethylene (TFE) and the perfluorinated vinyl etherCF₂═CF—O—CF₂CF(CF₃)—O—CF₂CF₂SO₂F,perfluoro(3,6-dioxa-4-methyl-7-octenesulfonyl fluoride) (PDMOF),followed by conversion to sulfonate groups by hydrolysis of the sulfonylfluoride groups and ion exchanged as necessary to convert them to thedesired ionic form. An example of a polymer of the type disclosed inU.S. Pat. Nos. 4,358,545 and 4,940,525 has the side chain—O—CF₂CF₂SO₃E⁵, wherein E⁵ is as defined above. This polymer can be madeby copolymerization of tetrafluoroethylene (TFE) and the perfluorinatedvinyl ether CF₂═CF—O—CF₂CF₂SO₂F, perfluoro(3-oxa-4-pentenesulfonylfluoride) (POPF), followed by hydrolysis and further ion exchange asnecessary.

In one embodiment, the FSA polymers for use in this invention typicallyhave an ion exchange ratio of less than about 33. In this application,“ion exchange ratio” or “IXR” is defined as number of carbon atoms inthe polymer backbone in relation to the cation exchange groups. Withinthe range of less than about 33, IXR can be varied as desired for theparticular application. In one embodiment, the IXR is about 3 to about33, and in another embodiment from about 8 to about 23.

The cation exchange capacity of a polymer is often expressed in terms ofequivalent weight (EW). For the purposes of this application, equivalentweight (EW) is defined to be the weight of the polymer in acid formrequired to neutralize one equivalent of sodium hydroxide. In the caseof a sulfonate polymer where the polymer has a perfluorocarbon backboneand the side chain is —O—CF₂—CF(CF₃)—O—CF₂—CF₂—SO₃H (or a salt thereof),the equivalent weight range which corresponds to an IXR of about 8 toabout 23 is about 750 EW to about 1500 EW. IXR for this polymer can berelated to equivalent weight using the formula: 50 IXR+344=EW. While thesame IXR range is used for sulfonate polymers disclosed in U.S. Pat.Nos. 4,358,545 and 4,940,525, e.g., the polymer having the side chain—O—CF₂CF₂SO₃H (or a salt thereof), the equivalent weight is somewhatlower because of the lower molecular weight of the monomer unitcontaining a cation exchange group. For the preferred IXR range of about8 to about 23, the corresponding equivalent weight range is about 575 EWto about 1325 EW. IXR for this polymer can be related to equivalentweight using the formula: 50 IXR+178=EW.

The FSA polymers can be prepared as colloidal aqueous dispersions. Theymay also be in the form of dispersions in other media, examples of whichinclude, but are not limited to, alcohol, water-soluble ethers, such astetrahydrofuran, mixtures of water-soluble ethers, and combinationsthereof. In making the dispersions, the polymer can be used in acidform. U.S. Pat. Nos. 4,433,082, 6,150,426 and WO 03/006537 disclosemethods for making of aqueous alcoholic dispersions. After thedispersion is made, the concentration and the dispersing liquidcomposition can be adjusted by methods known in the art.

Aqueous dispersions of the colloid-forming polymeric acids, includingFSA polymers, typically have particle sizes as small as possible and anEW as small as possible, so long as a stable colloid is formed.

Aqueous dispersions of FSA polymer are available commericially asNafion® dispersions, from E.I. du Pont de Nemours and Company(Wilmington, Del.).

4. Preparing Doped Semiconductive Polymers

In one embodiment, the doped semiconductive polymers are formed byoxidative polymerization of the precursor monomer in the presence of atleast one FAP. The doped semiconductive polymers are abbreviatedhereinafter as “SCP/FAP”. The polymerization is generally carried out ina homogeneous aqeuous solution. In another embodiment, thepolymerization for obtaining the electrically conducting polymer iscarried out in an emulsion of water and an organic solvent. In general,some water is present in order to obtain adequate solubility of theoxidizing agent and/or catalyst. Oxidizing agents such as ammoniumpersulfate, sodium persulfate, potassium persulfate, and the like, canbe used. A catalyst, such as ferric chloride, or ferric sulfate may alsobe present. The resulting polymerized product will be a solution,dispersion, or emulsion of the doped semiconductive polymer.

In one embodiment, the method of making an aqueous dispersion of thesemiconductive polymer doped with FAP includes forming a reactionmixture by combining water, at least one precursor monomer, at least oneFAP, and an oxidizing agent, in any order, provided that at least aportion of the FAP is present when at least one of the precursor monomerand the oxidizing agent is added. It will be understood that, in thecase of semiconductive copolymers, the term “at least one precursormonomer” encompasses more than one type of monomer.

In one embodiment, the method of making an aqueous dispersion of thedoped semiconductive polymer includes forming a reaction mixture bycombining water, at least one precursor monomer, at least one FAP, andan oxidizing agent, in any order, provided that at least a portion ofthe FAP is present when at least one of the precursor monomer and theoxidizing agent is added.

In one embodiment, the method of making the doped semiconductive polymercomprises:

-   -   (a) providing an aqueous solution or dispersion of a FAP;    -   (b) adding an oxidizer to the solutions or dispersion of step        (a); and    -   (c) adding at least one precursor monomer to the mixture of step        (b).

In another embodiment, the precursor monomer is added to the aqueoussolution or dispersion of the FAP prior to adding the oxidizer. Step (b)above, which is adding oxidizing agent, is then carried out.

In another embodiment, a mixture of water and the precursor monomer isformed, in a concentration typically in the range of from about 0.5% byweight to about 4.0% by weight total precursor monomer. This precursormonomer mixture is added to the aqueous solution or dispersion of theFAP, and steps (b) above which is adding oxidizing agent is carried out.

In another embodiment, the aqueous polymerization mixture may include apolymerization catalyst, such as ferric sulfate, ferric chloride, andthe like. The catalyst is added before the last step. In anotherembodiment, a catalyst is added together with an oxidizing agent.

In one embodiment, the polymerization is carried out in the presence ofco-dispersing liquids which are miscible with water. Examples ofsuitable co-dispersing liquids include, but are not limited to ethers,alcohols, alcohol ethers, cyclic ethers, ketones, nitrites, sulfoxides,amides, and combinations thereof. In one embodiment, the co-dispersingliquid is an alcohol. In one embodiment, the co-dispersing liquid is anorganic solvent selected from n-propanol, isopropanol, t-butanol,dimethylacetamide, dimethylformamide, N-methylpyrrolidone, and mixturesthereof. In general, the amount of co-dispersing liquid should be lessthan about 60% by volume. In one embodiment, the amount of co-dispersingliquid is less than about 30% by volume. In one embodiment, the amountof co-dispersing liquid is between 5 and 50% by volume. The use of aco-dispersing liquid in the polymerization significantly reducesparticle size and improves filterability of the dispersions. Inaddition, buffer materials obtained by this process show an increasedviscosity and films prepared from these dispersions are of high quality.

The co-dispersing liquid can be added to the reaction mixture at anypoint in the process.

In one embodiment, the polymerization is carried out in the presence ofa co-acid which is a Brønsted acid. The acid can be an inorganic acid,such as HCl, sulfuric acid, and the like, or an organic acid, such asacetic acid or p-toluenesulfonic acid. Alternatively, the acid can be awater soluble polymeric acid such as poly(styrenesulfonic acid),poly(2-acrylamido-2-methyl-1-propanesulfonic acid, or the like, or asecond fluorinated acid polymer, as described above. Combinations ofacids can be used.

The co-acid can be added to the reaction mixture at any point in theprocess prior to the addition of either the oxidizer or the precursormonomer, whichever is added last. In one embodiment, the co-acid isadded before both the precursor monomers and the fluorinated acidpolymer, and the oxidizer is added last. In one embodiment the co-acidis added prior to the addition of the precursor monomers, followed bythe addition of the fluorinated acid polymer, and the oxidizer is addedlast.

In one embodiment, the polymerization is carried out in the presence ofboth a co-dispersing liquid and a co-acid.

In the method of making the doped semiconductive polymer, the molarratio of oxidizer to total precursor monomer is generally in the rangeof 0.1 to 3.0; and in one embodiment is 0.4 to 1.5. The molar ratio ofFAP to total precursor monomer is generally in the range of from 0.2 to10. In one embodiment, the ratio is in the range of 1 to 5. The overallsolid content is generally in the range of about 0.5% to 12% in weightpercentage; and in one embodiment of about 2% to 6%. The reactiontemperature is generally in the range of about 4° C. to 50° C.; in oneembodiment about 20° C. to 35° C. The molar ratio of optional co-acid toprecursor monomer is about 0.05 to 4. The addition time of the oxidizerinfluences particle size and viscosity. Thus, the particle size can bereduced by slowing down the addition speed. In parallel, the viscosityis increased by slowing down the addition speed. The reaction time isgenerally in the range of about 1 to about 30 hours.

(a) pH Treatment

As synthesized, the aqueous dispersions of the doped semiconductivepolymers generally have a very low pH. When the semiconductive polymeris doped with a FAP, it has been found that the pH can be adjusted tohigher values, without adversely affecting the properties in devices. Inone embodiment, the pH of the dispersion can be adjusted to about 1.5 toabout 4. In one embodiment, the pH is adjusted to between 2 and 3. Ithas been found that the pH can be adjusted using known techniques, forexample, ion exchange or by titration with an aqueous basic solution.

In one embodiment, the as-formed aqueous dispersion of FAP-dopedsemiconductive polymer is contacted with at least one ion exchange resinunder conditions suitable to remove any remaining decomposed species,side reaction products, and unreacted monomers, and to adjust pH, thusproducing a stable, aqueous dispersion with a desired pH. In oneembodiment, the as-formed doped semiconductive polymer dispersion iscontacted with a first ion exchange resin and a second ion exchangeresin, in any order. The as-formed doped semiconductive polymerdispersion can be treated with both the first and second ion exchangeresins simultaneously, or it can be treated sequentially with one andthen the other. In one embodiment, the two doped semiconductive polymersare combined as-synthesized, and then treated with one or more ionexchange resins.

Ion exchange is a reversible chemical reaction wherein an ion in a fluidmedium (such as an aqueous dispersion) is exchanged for a similarlycharged ion attached to an immobile solid particle that is insoluble inthe fluid medium. The term “ion exchange resin” is used herein to referto all such substances. The resin is rendered insoluble due to thecrosslinked nature of the polymeric support to which the ion exchanginggroups are attached. Ion exchange resins are classified as cationexchangers or anion exchangers. Cation exchangers have positivelycharged mobile ions available for exchange, typically protons or metalions such as sodium ions. Anion exchangers have exchangeable ions whichare negatively charged, typically hydroxide ions.

In one embodiment, the first ion exchange resin is a cation, acidexchange resin which can be in protonic or metal ion, typically sodiumion, form. The second ion exchange resin is a basic, anion exchangeresin. Both acidic, cation including proton exchange resins and basic,anion exchange resins are contemplated for use in the practice of theinvention. In one embodiment, the acidic, cation exchange resin is aninorganic acid, cation exchange resin, such as a sulfonic acid cationexchange resin. Sulfonic acid cation exchange resins contemplated foruse in the practice of the invention include, for example, sulfonatedstyrene-divinylbenzene copolymers, sulfonated crosslinked styrenepolymers, phenol-formaldehyde-sulfonic acid resins,benzene-formaldehyde-sulfonic acid resins, and mixtures thereof. Inanother embodiment, the acidic, cation exchange resin is an organicacid, cation exchange resin, such as carboxylic acid, acrylic orphosphorous cation exchange resin. In addition, mixtures of differentcation exchange resins can be used.

In another embodiment, the basic, anionic exchange resin is a tertiaryamine anion exchange resin. Tertiary amine anion exchange resinscontemplated for use in the practice of the invention include, forexample, tertiary-aminated styrene-divinylbenzene copolymers,tertiary-aminated crosslinked styrene polymers, tertiary-aminatedphenol-formaldehyde resins, tertiary-aminated benzene-formaldehyderesins, and mixtures thereof. In a further embodiment, the basic,anionic exchange resin is a quaternary amine anion exchange resin, ormixtures of these and other exchange resins.

The first and second ion exchange resins may contact the as-formedaqueous dispersion either simultaneously, or consecutively. For example,in one embodiment both resins are added simultaneously to an as-formedaqueous dispersion of an electrically conducting polymer, and allowed toremain in contact with the dispersion for at least about 1 hour, e.g.,about 2 hours to about 20 hours. The ion exchange resins can then beremoved from the dispersion by filtration. The size of the filter ischosen so that the relatively large ion exchange resin particles will beremoved while the smaller dispersion particles will pass through.Without wishing to be bound by theory, it is believed that the ionexchange resins quench polymerization and effectively remove ionic andnon-ionic impurities and most of unreacted monomer from the as-formedaqueous dispersion. Moreover, the basic, anion exchange and/or acidic,cation exchange resins renders the acidic sites more basic, resulting inincreased pH of the dispersion. In general, about one to five grams ofion exchange resin is used per gram of semiconductive polymercomposition.

In many cases, the basic ion exchange resin can be used to adjust the pHto the desired level. In some cases, the pH can be further adjusted withan aqueous basic solution such as a solution of sodium hydroxide,ammonium hydroxide, tetra-methylammonium hydroxide, or the like.

5. Preparing Buffer Compositions

The new buffer compositions can be formed by blending the semiconductiveoxide particles with the FAP or the SCP/FAP. This can be accomplished byadding an aqueous dispersion of the semiconductive oxide particles to anaqueous dispersion of the FAP or the SCP/FAP. In one embodiment, thecomposition is further treated using sonication or microfluidization toensure mixing of the components.

In one embodiment, one or both of the components are isolated in solidform. The solid material can be redispersed in water or in an aqueoussolution or dispersion of the other component. For example,semiconductive oxide particle solids can be dispersed in an aqueoussolution or dispersion of a semiconductive polymer doped with an FAP.

6. Buffer Layers

In another embodiment of the invention, there are provided buffer layersdeposited from aqueous dispersions comprising the new buffercompositions. The term “buffer layer” or “buffer material” is intendedto mean electrically conductive or semiconductive materials and may haveone or more functions in an organic electronic device, including but notlimited to, planarization of the underlying layer, charge transportand/or charge injection properties, scavenging of impurities such asoxygen or metal ions, and other aspects to facilitate or to improve theperformance of the organic electronic device. The term “layer” is usedinterchangeably with the term “film” and refers to a coating covering adesired area. The sense of the term is not limited or qualified byconsiderations of the size of a coated area. The area can be as large asan entire device or as small as a specific functional area such as theactual visual display, or as small as a single sub-pixel.

In one embodiment, the buffer layer is formed using a liquid depositionmethod. Any liquid deposition method can be used. Continuous liquiddeposition techniques, inlcude but are not limited to, spin coating,gravure coating, curtain coating, dip coating, slot-die coating, spraycoating, and continuous nozzle coating. Discontinuous liquid depositiontechniques include, but are not limited to, ink jet printing, gravureprinting, and screen printing.

In another embodiment, there are provided buffer layers deposited fromaqueous dispersions comprising the new conductive polymer compositionblended with other water soluble or dispersible materials. Examples oftypes of materials which can be added include, but are not limited topolymers, dyes, coating aids, organic and inorganic conductive inks andpastes, charge transport materials, crosslinking agents, andcombinations thereof. The other water soluble or dispersible materialscan be simple molecules or polymers. Examples of suitable polymersinclude, but are not limited to, conductive polymers such aspolythiophenes, polyanilines, polypyrroles, polyacetylenes, andcombinations thereof.

7. Electronic Devices

In another embodiment of the invention, there are provided electronicdevices comprising at least one electroactive layer positioned betweentwo electrical contact layers, wherein the device further includes thenew buffer layer. The term “electroactive” when referring to a layer ormaterial is intended to mean a layer or material that exhibitselectronic or electro-radiative properties. An electroactive layermaterial may emit radiation or exhibit a change in concentration ofelectron-hole pairs when receiving radiation.

As shown in FIG. 2, a typical device, 100, has an anode layer 110, abuffer layer 120, an electroactive layer 130, and a cathode layer 150.Adjacent to the cathode layer 150 is an optionalelectron-injection/transport layer 140.

The device may include a support or substrate (not shown) that can beadjacent to the anode layer 110 or the cathode layer 150. Mostfrequently, the support is adjacent the anode layer 110. The support canbe flexible or rigid, organic or inorganic. Examples of supportmaterials include, but are not limited to, glass, ceramic, metal, andplastic films.

The anode layer 110 is an electrode that is more efficient for injectingholes compared to the cathode layer 150. The anode can include materialscontaining a metal, mixed metal, alloy, metal oxide or mixed oxide.Suitable materials include the mixed oxides of the Group 2 elements(i.e., Be, Mg, Ca, Sr, Ba, Ra), the Group 11 elements, the elements inGroups 4, 5, and 6, and the Group 8-10 transition elements. If the anodelayer 110 is to be light transmitting, mixed oxides of Groups 12, 13 and14 elements, such as indium-tin-oxide, may be used. As used herein, thephrase “mixed oxide” refers to oxides having two or more differentcations selected from the Group 2 elements or the Groups 12, 13, or 14elements. Some non-limiting, specific examples of materials for anodelayer 110 include, but are not limited to, indium-tin-oxide (“ITO”),indium-zinc-oxide, aluminum-tin-oxide, gold, silver, copper, and nickel.The anode may also comprise an organic material, especially a conductingpolymer such as polyaniline, including exemplary materials as describedin “Flexible light-emitting diodes made from soluble conductingpolymer,” Nature vol. 357, pp 477 479 (11 Jun. 1992). At least one ofthe anode and cathode should be at least partially transparent to allowthe generated light to be observed.

The anode layer 110 may be formed by a chemical or physical vapordeposition process or spin-cast process. Chemical vapor deposition maybe performed as a plasma-enhanced chemical vapor deposition (“PECVD”) ormetal organic chemical vapor deposition (“MOCVD”). Physical vapordeposition can include all forms of sputtering, including ion beamsputtering, as well as e-beam evaporation and resistance evaporation.Specific forms of physical vapor deposition include rf magnetronsputtering and inductively-coupled plasma physical vapor deposition(“IMP-PVD”). These deposition techniques are well known within thesemiconductor fabrication arts.

In one embodiment, the anode layer 110 is patterned during alithographic operation. The pattern may vary as desired. The layers canbe formed in a pattern by, for example, positioning a patterned mask orresist on the first flexible composite barrier structure prior toapplying the first electrical contact layer material. Alternatively, thelayers can be applied as an overall layer (also called blanket deposit)and subsequently patterned using, for example, a patterned resist layerand wet chemical or dry etching techniques. Other processes forpatterning that are well known in the art can also be used.

The buffer layer 120 is usually deposited onto substrates using avariety of techniques well-known to those skilled in the art. Typicaldeposition techniques, as discussed above, include liquid deposition(continuous and discontinuous techniques), and thermal transfer.

An optional layer, not shown, may be present between the buffer layer120 and the electroactive layer 130. This layer may comprise holetransport materials. Examples of hole transport materials for layer 120have been summarized for example, in Kirk-Othmer Encyclopedia ofChemical Technology, Fourth Edition, Vol. 18, p. 837-860, 1996, by Y.Wang. Both hole transporting molecules and polymers can be used.Commonly used hole transporting molecules include, but are not limitedto: 4,4′,4″-tris(N,N-diphenyl-amino)-triphenylamine (TDATA);4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine (MTDATA);N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine(TPD); 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC);N,N′-bis(4-methylphenyl)-N,N′-bis(4-ethylphenyl)-[1,1′-(3,3′-dimethyl)biphenyl]-4,4′-diamine(ETPD); tetrakis-(3-methylphenyl)-N,N, N′,N′-2,5-phenylenediamine (PDA);α-phenyl-4-N,N-diphenylaminostyrene (TPS); p-(diethylamino)benzaldehydediphenylhydrazone (DEH); triphenylamine (TPA);bis[4-(N,N-diethylamino)-2-methylphenyl](4-methylphenyl)methane (MPMP);1-phenyl-3-[p-(diethylamino)styryl]-5-[p-(diethylamino)phenyl]pyrazoline(PPR or DEASP); 1,2-trans-bis(9H-carbazol-9-yl)cyclobutane (DCZB);N,N,N′,N′-tetrakis(4-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine (TTB);N,N′-bis(naphthalen-1-yl)-N,N′-bis-(phenyl)benzidine (α-NPB); andporphyrinic compounds, such as copper phthalocyanine. Commonly used holetransporting polymers include, but are not limited to,poly(9,9,-dioctylfluorene-co-N-(4-butylphenyl)diphenylaminer), and thelike, polyvinylcarbazole, (phenylmethyl)polysilane,poly(dioxythiophenes), polyanilines, and polypyrroles. It is alsopossible to obtain hole transporting polymers by doping holetransporting molecules such as those mentioned above into polymers suchas polystyrene and polycarbonate.

Depending upon the application of the device, the electroactive layer130 can be a light-emitting layer that is activated by an appliedvoltage (such as in a light-emitting diode or light-emittingelectrochemical cell), a layer of material that responds to radiantenergy and generates a signal with or without an applied bias voltage(such as in a photodetector). In one embodiment, the electroactivematerial is an organic electroluminescent (“EL”) material. Any ELmaterial can be used in the devices, including, but not limited to,small molecule organic fluorescent compounds, fluorescent andphosphorescent metal complexes, conjugated polymers, and mixturesthereof. Examples of fluorescent compounds include, but are not limitedto, pyrene, perylene, rubrene, coumarin, derivatives thereof, andmixtures thereof. Examples of metal complexes include, but are notlimited to, metal chelated oxinoid compounds, such astris(8-hydroxyquinolato)aluminum (Alq3); cyclometalated iridium andplatinum electroluminescent compounds, such as complexes of iridium withphenylpyridine, phenylquinoline, or phenylpyrimidine ligands asdisclosed in Petrov et al., U.S. Pat. No. 6,670,645 and Published PCTApplications WO 03/063555 and WO 2004/016710, and organometalliccomplexes described in, for example, Published PCT Applications WO03/008424, WO 03/091688, and WO 03/040257, and mixtures thereof.Electroluminescent emissive layers comprising a charge carrying hostmaterial and a metal complex have been described by Thompson et al., inU.S. Pat. No. 6,303,238, and by Burrows and Thompson in published PCTapplications WO 00/70655 and WO 01/41512. Examples of conjugatedpolymers include, but are not limited to poly(phenylenevinylenes),polyfluorenes, poly(spirobifluorenes), polythiophenes,poly(p-phenylenes), copolymers thereof, and mixtures thereof.

Optional layer 140 can function both to facilitate electroninjection/transport, and can also serve as a confinement layer toprevent quenching reactions at layer interfaces. More specifically,layer 140 may promote electron mobility and reduce the likelihood of aquenching reaction if layers 130 and 150 would otherwise be in directcontact. Examples of materials for optional layer 140 include, but arenot limited to, metal chelated oxinoid compounds, such asbis(2-methyl-8-quinolinolato)(para-phenyl-phenolato)aluminum(III)(BAIQ), tetra(8-hydroxyquinolato)zirconium (ZrQ), andtris(8-hydroxyquinolato)aluminum (Alq₃); azole compounds such as2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole (PBD),3-(4-biphenylyl)-4-phenyl-5-(4-t-butylphenyl)-1,2,4-triazole (TAZ), and1,3,5-tri(phenyl-2-benzimidazole)benzene (TPBI); quinoxaline derivativessuch as 2,3-bis(4-fluorophenyl)quinoxaline; phenanthroline derivativessuch as 9,10-diphenylphenanthroline (DPA) and2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (DDPA); and any one ormore combinations thereof. Alternatively, optional layer 140 may beinorganic and comprise BaO, LiF, Li₂O, or the like.

The cathode layer 150 is an electrode that is particularly efficient forinjecting electrons or negative charge carriers. The cathode layer 150can be any metal or nonmetal having a lower work function than the firstelectrical contact layer (in this case, the anode layer 110).

Materials for the cathode layer can be selected from alkali metals ofGroup 1 (e.g., Li, Na, K, Rb, Cs,), the Group 2 metals (e.g., Mg, Ca,Ba, or the like), the Group 12 metals, the lanthanides (e.g., Ce, Sm,Eu, or the like), and the actinides (e.g., Th, U, or the like).Materials such as aluminum, indium, yttrium, and combinations thereof,may also be used. Specific non-limiting examples of materials for thecathode layer 150 include, but are not limited to, barium, lithium,cerium, cesium, europium, rubidium, yttrium, magnesium, samarium, andalloys and combinations thereof.

The cathode layer 150 is usually formed by a chemical or physical vapordeposition process. In some embodiments, the cathode layer will bepatterned, as discussed above in reference to the anode layer 110.

Other layers in the device can be made of any materials which are knownto be useful in such layers upon consideration of the function to beserved by such layers.

In some embodiments, an encapsulation layer (not shown) is depositedover the contact layer 150 to prevent entry of undesirable components,such as water and oxygen, into the device 100. Such components can havea deleterious effect on the organic layer 130. In one embodiment, theencapsulation layer is a barrier layer or film. In one embodiment, theencapsulation layer is a glass lid.

Though not depicted, it is understood that the device 100 may compriseadditional layers. Other layers that are known in the art or otherwisemay be used. In addition, any of the above-described layers may comprisetwo or more sub-layers or may form a laminar structure. Alternatively,some or all of anode layer 110 the buffer layer 120, the electrontransport layer 140, cathode layer 150, and other layers may be treated,especially surface treated, to increase charge carrier transportefficiency or other physical properties of the devices. The choice ofmaterials for each of the component layers is preferably determined bybalancing the goals of providing a device with high device efficiencywith device operational lifetime considerations, fabrication time andcomplexity factors and other considerations appreciated by personsskilled in the art. It will be appreciated that determining optimalcomponents, component configurations, and compositional identities wouldbe routine to those of ordinary skill of in the art.

In various embodiments, the different layers have the following rangesof thicknesses: anode 110, 500-5000 Å, in one embodiment 1000-2000 Å;buffer layer 120, 50-2000 Å, in one embodiment 200-1000 Å; optionaltransport layer, 50-2000 Å, in one embodiment 100-1000 Å; photoactivelayer 130, 10-2000 Å, in one embodiment 100-1000 Å; optional electrontransport layer 140, 50-2000 Å, in one embodiment 100-1000 Å; cathode150, 200-10000 Å, in one embodiment 300-5000 Å. The location of theelectron-hole recombination zone in the device, and thus the emissionspectrum of the device, can be affected by the relative thickness ofeach layer. Thus the thickness of the electron-transport layer should bechosen so that the electron-hole recombination zone is in thelight-emitting layer. The desired ratio of layer thicknesses will dependon the exact nature of the materials used.

In operation, a voltage from an appropriate power supply (not depicted)is applied to the device 100. Current therefore passes across the layersof the device 100. Electrons enter the organic polymer layer, releasingphotons. In some OLEDs, called active matrix OLED displays, individualdeposits of photoactive organic films may be independently excited bythe passage of current, leading to individual pixels of light emission.In some OLEDs, called passive matrix OLED displays, deposits ofphotoactive organic films may be excited by rows and columns ofelectrical contact layers.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

As used herein, the term “layer” is used interchangeably with the term“film” and refers to a coating covering a desired area. The meaning isnot affected by the size of the area coated. The area can be as large asan entire device or as small as a specific functional area such as theactual visual display, or as small as a single sub-pixel. Layers andfilms can be formed by any conventional deposition technique, includingvapor deposition, liquid deposition (continuous and discontinuoustechniques), and thermal transfer. Continuous deposition techniques,inlcude but are not limited to, spin coating, gravure coating, curtaincoating, dip coating, slot-die coating, spray coating, and continuousnozzle coating. Discontinuous deposition techniques include, but are notlimited to, ink jet printing, gravure printing, and screen printing.

The term “work function” is intended to mean the minimum energy neededto remove an electron from a material to a point at infinite distanceaway from the surface.

Also, use of “a” or “an” are employed to describe elements andcomponents of the invention. This is done merely for convenience and togive a general sense of the invention. This description should be readto include one or at least one and the singular also includes the pluralunless it is obvious that it is meant otherwise.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of the present invention, suitable methods andmaterials are described below. All publications, patent applications,patents, and other references mentioned herein are incorporated byreference in their entirety. In case of conflict, the presentspecification, including definitions, will control. In addition, thematerials, methods, and examples are illustrative only and not intendedto be limiting.

EXAMPLES Example 1

This example illustrates preparation of an aqueous dispersion ofantimony double oxide with Nafion®, and conductivity of the filmspin-coated from the dispersion. Nafion® is a trade name forpoly(perfluoroethylene sulfonic acid) from E.I. du Pont de Nemours andCompany (Wilmington, Del.):

In this example, Celnax CX-Z300H purchased from Nissan ChemicalIndustries, LTD from Houston, Tex. The Celnax is antimony double oxidehydrosol, which contains 30% (w/w) oxide and about 70% water. It has pH6.9 and particle size of 20 nm using BET method. Thin layer of driedfilm of the material is bluish green color and almost transparent.2.0112 g of Celnax was first diluted with 4.9748 g de-ionized water.1.632 g Nafion® dispersion, which contains 12.23% (w/w) Nafion® polymer,was then added to the diluted Celnax dispersion. They mixed easily andformed a stable dispersion without a sign of sedimentation.

A couple of drops of the dispersion were placed on a microscope slide toform a thin, transparent film. The thin film was painted with silverpaste to form two parallel lines as electrodes for measurement ofresistance. The resistance was converted to conductivity by taking athickness of the film and separating the two electrodes along the lengthof the electrodes. Conductivity was determined to be 8×10⁴S/cm. Thisconductivity is suitable as a buffer layer.

The dried film will be measured for Wf by Ultraviolet PhotoelctronSpectroscopy (UPS). Wf energy level is usually determined from secondelectron cut-off with respect to the position of vacuum level using He I(21.22 eV) radiation.

Example 2

This example illustrates effect on work-function of the addition ofNafion® to a semiconductive oxide dispersion. Nafion® is a trademark forpoly(perfluoroethylenesulfonic acid) from E.I. du Pont de Nemours andCompany.

General Procedure of Film Sample Preparation and Kelvin ProbeMeasurement

Film samples of Kelvin probe measurement for determination ofwork-function were made by spin-coating of a semiconductive dispersionor an admixture dispersion on 30 mm×30 mm glass/ITO substrates.ITO/glass substrates consist of 15 mm×20 mm ITO area at the centerhaving ITO thickness of from 100 to 150 nm. At one corner of 15 mm×20 mmITO area, ITO film surface extended to the edge of the glass/ITO servesas electrical contact with Kelvin probe electrode. Prior to spincoating, ITO/glass substrates were cleaned and the ITO sides weresubsequently treated with UV-ozone for 10 minutes. Once spin-coated, thedeposited materials on the corner of the extended ITO film were removedwith a Q-tip wetted with ether water. The exposed ITO pad was for makingcontact with Kelvin probe electrode. The deposited films were then bakedas illustrated in Examples. The baked film samples were then placed on aglass jug flooded with nitrogen before capped with a lid beforemeasurement.

For work-function determination, an ambient-aged gold film was measuredfirst as a reference prior to measurement of samples. The gold film on asame size of glass piece was placed in a cavity cut out at the bottom ofa square steel container. On the side of the cavity, there are fourretention clips to keep sample piece firmly in place. One of theretention clips is attached with electrical wire for making contact withthe Kelvin probe. The gold film was facing up while a Kelvin probe tipprotruded from the center of a steel lid was lowered to above the centerof the gold film surface. The lid was then screwed tightly onto thesquare steel container at four corners. A side port on the square steelcontainer was connected with tubing for allowing nitrogen to sweep theKelvin probe cell continuously while a nitrogen exit port capped with aseptum in which a steel needle is inserted for maintaining ambientpressure. The probe settings were then optimized for the probe and onlyheight of the tip was changed through entire measurement. The Kelvinprobe was connected to a McAllister KP6500 Kelvin Probe meter having thefollowing parameters: 1) frequency: 230; 2) amplitude: 20; 3) DC offset:varied from sample to sample; 4) upper backing potential: 2 volt; 5)lower backing potential: −2 volt; 6) scan rate: 1; 7) trigger delay: 0;8) acquisition(A)/data(D) points:1024; 9) A/D rate: 12405 @19.0 cycles;10) D/A: delay: 200; 11) set point gradient: 0.2; 12) step size: 0.001;13) maximum gradient deviation: 0.001. As soon as the tracking gradientstabilized, the contact potential difference (“CPD”) in volt betweengold film was recorded. The CPD of gold was then referencing the probetip to (4.7-CPD) eV. The 4.7 eV (electron volt) is work-function ofambient aged gold film surface [Surface Science, 316, (1994), P380]. TheCPD of gold was measured periodically while CPD of samples were beingdetermined. Each sample was loaded into the cavity in the same manner asgold film sample with the four retention clips. On the retention clipmaking electrical contact with the sample care was taken to make suregood electrical contact was made with the exposed ITO pad at one corner.During the CPD measurement a small stream of nitrogen was flowed throughthe cell continuously without disturbing the probe tip. Once CPD ofsample was recorded, the sample workfunction or energy potential wasthen calculated by adding CPD of the sample to the difference of 4.7 eVand CPD of gold.

In this example, Celnax CX-Z300H used for illustration was alsopurchased from Nissan Chemical Industries, LTD from Houston, Tex. TheCelnax is antimony double oxide (antimony zirconate) hydrosol, which wasdetermined to contain 27.05% (w/w) oxide and the rest is water. It haspH 6.9 and particle size of 20 nm using BET method. To determinework-function of the semiconductive oxide film, a diluted CX-Z300H wasmade by mixing 5.004 g of the hydrosol with 13.828 g deionized water.The diluted sample contains only 7.19% (w/w) oxide. It was spin-coatedat a speed of 1,800 rpm for 60 seconds on one of the ITO substratesdescribed in the general procedure of film sample preparation. Thezinc/antimony double oxide film on the ITO/glass substrate was thenbaked at 130° C. in air for 10 minutes. Prior to Kelvin probemeasurement of the oxide film sample, a gold film was measured first.Contact potential difference (CPD) between gold film and the Kelvinprobe tip is 0.663 volt. CPD between the oxide film and Kelvin probe tipwas determined to be 0.87 volt. Work-function of the antimony oxidesurface was therefore calculated to be 4.91 eV using 4.7 eV forwork-function of air-aged gold. This work-function (Wf) data is listedin Table 1 as a control to determine effect of addition of Nafion® onits work-function.

Nafion® used for addition to CX-Z300H has an EW of 1000 and was madeusing a procedure similar to the procedure in U.S. Pat. No. 6,150,426,Example 1, Part 2, except that the temperature is approximately 270° C.As made Nafion® is at 25% (w/w) in water. The 25% dispersion was firstdiluted to 12% before use. The general procedure for making the mixturewas to add the Nafion® to CX-Z300H which was diluted with water first.Final solid concentration was aimed at about 7.2% (w/w) in water, butthe ratio of acid-equivalent/1 g double oxide was kept at five differentlevels. For the example of 5.0×10⁻⁴ acid-equivalent/1 g antimony/zincoxide, 5.0091 g CX-Z300H was added with 17.6691 g deionized water. Itwas stirred with a roller and then added with 5.6859 g Nafion®. Thefinal solid concentration is 7.18% and the acid-equivalent/1 g oxide is5.0×10⁻⁴. Each dispersion sample listed in Table 1 was made in the samemanner and was filtered through a 0.45 μm HV filter onto anozone-treated ITO substrate for spin-coating at 1,800 RPM for 60seconds. The spin-coated films were then baked at 130° C. in air for 10minutes and measured for contact potential difference with Kelvin probe.Table 1 clearly shows that work-function of antimony/zinc double oxidefilm surface is low, but increases as Nafion® is added to CX-Z300H. Highwork-function is critical for OLEDs as a buffer layer for devicefunction. TABLE 1 Effect of acid (Nafion ®) equivalent/1 gram-oxide onwork-function (Wf) Acid equivalent./1 g oxide CPD (volt) Wf (eV, ref. ToAu) 0 0.87 4.91   1 × 10⁻⁴ 1.02 5.06 2.6 × 10⁻⁴ 1.37 5.41 5.0 × 10⁻⁴1.60 5.64 7.2 × 10⁻⁴ 1.77 5.81 2.5 × 10⁻³ 1.99 6.03

Example 3

This example illustrates the effect of the addition of Poly(VF2/PSEBVE)to a semiconductive oxide dispersion on its work-function.

In this example, Celnax CX-Z300H was also used to determine effect ofpoly(VF2/PSEBVE) on work-function of zinc/antimoney double oxide.Synthesis of of Poly(VF2/PSEBVE) was illustrated later in this example.The procedure described in Example 2 for film preparation ofzinc/antimony oxide, and its admixture with Poly(VF2/PSEBVE), andcontact potential difference measurement for determination ofwork-function was closely followed. The work-function data listed inTable 2 clearly shows that work-function of antimony/zinc double oxidefilm surface is low, but increase as Nafion® is added to CX-Z300H. Highwork-function is critical for OLEDs as a buffer layer for devicefunction.

Poly(VF2/PSEBVE) used for adding to Celnax CX-Z300H was made as follows.

a) Synthesis of an organic solvent wettable Poly(VF2/PSEBVE) of1,1-difluoroethylene (“VF2”) and2-(1,1-difluoro-2-(trifluoromethyl)allyloxy)-1,1,2,2-tetrafluoroethanesulfonylfluoride (“PSEBVE”)

A 400 mL Hastelloy C276 reaction vessel was charged with 160 mL ofVertrel® XF, 4 mL of a 20 wt. % solution of HFPO dimer peroxide inVertrel® XF, and 143 g of PSEBVE (0.42 mol). The vessel was cooled to−35° C., evacuated to −3 PSIG, and purged with nitrogen. Theevacuate/purge cycle was repeated two more times. To the vessel was thenadded 29 g VF₂ (0.45 mol). The vessel was heated to 28° C., whichincreased the pressure to 92 PSIG. The reaction temperature wasmaintained at 28° C. for 18 h. at which time the pressure had dropped to32 PSIG. The vessel was vented and the crude liquid material wasrecovered. The Vertrel® XF was removed in vacuo to afford 110 g ofdesired copolymer.

b) Conversion of the Sulfonyl Fluoride Copolymer Prepared Above toSulfonic Acid:

20 g of dried polymer and 5.0 g lithium carbonate were refluxed in 100mL dry methanol for 12 h. The mixture was brought to room temperatureand filtered to remove any remaining solids. The methanol was removed invacuo to isolate the lithium salt of the polymer. The lithium salt ofthe polymer was then dissolved in water and added with Amberlyst 15, aprotonic acid exchange resin which had been washed thoroughly with wateruntil there was no color in the water. The mixture was stirred andfiltered. Filtrate was added with fresh Amberlyst 15 resin and filteredagain. The step was repeated two more times. Water was then removed fromthe final filtrates and the solids were then dried in a vacuum oven.

Films made from VF₂-PSEBVE acid are wettable by organic solvents.Phenylhexane will have a contact angle less than 40° on the films. TABLE2 Effect of acid [poly(VF2/PSEBVE)] equivalent/gram-oxide onwork-function Acid equivalent/1 g oxide CPD Wf (eV, ref. To Au) 0 0.874.91 1.0 × 10⁻⁴ 1.29 5.34 2.5 × 10⁻⁴ 1.56 5.61 5.0 × 10⁻⁴ 1.79 5.84 1.0× 10⁻³ 1.98 6.06 1.7 × 10⁻³ 2.06 6.13

Example 4

This example illustrates the effect of the addition of Poly(E/PSEPVE) toa semicondutive oxide dispersion on its work-function. In this example,Celnax CX-Z300H was also used to determine effect of poly(E/PSEPVE) onwork-function of zinc/antimoney double oxide. Synthesis of ofPoly(E/PSEPVE) was described later in this example. The proceduredescribed in Example 2 for film preparation of zinc/antimony oxide, andits admixture with Poly(E/PSEPVE), and contact potential differencemeasurement for determination of work-function was closely followed. Thework-function data listed in Table 3 clearly shows that addition ofPoly(E/PSEPVE) to CX-Z300H has enhanced work-function of antimony/zincdouble oxide. High work-function is critical for OLEDs as a buffer layerfor device function.

Poly(E/PSEPVE) used for adding to Celnax CX-Z300H was made as follows.

a) Synthesis of an organic solvent wettable Poly(E/PSEPVE) of ethylene(“E”) and2-(2-(1,2,2-trifluorovinyloxy)-1,1,2,3,3,3-hexafluoropropoxy)-1,1,2,2-tetrafluoroethanesulfonylfluoride (“PSEPVE”)

A 210 mL Hastelloy C276 reaction vessel was charged with 60 g of PSEPVE(0.13 mol) and 1 mL of a 0.17 M solution of HFPO dimer peroxide inVertrel® XF. The vessel was cooled to −35° C., evacuated to −3 PSIG, andpurged with nitrogen. The evacuate/purge cycle was repeated two moretimes. To the vessel was then added 20 g ethylene (0.71 mol) and anadditional 900 PSIG of nitrogen gas. The vessel was heated to 24° C.,which increased the pressure to 1400 PSIG. The reaction temperature wasmaintained at 24° C. for 18 h. at which time the pressure had dropped to1350 PSIG. The vessel was vented and 61.4 g of crude material wasrecovered. 10 g of this material were dried at 85° C. and 20 milliTorrfor 10 h. to give 8.7 g of dried polymer.

B) Conversion of the Sulfonyl Fluoride Copolymer Prepared Above toSulfonic acid:

A mixture of 19.6 g of dried polymer and 5.6 g lithium carbonate wererefluxed in 300 mL dry methanol for 6 h. The mixture was brought to roomtemperature and filtered to remove any remaining solids. The methanolwas removed in vacuo to afford 15.7 g of the lithium salt of thepolymer. The lithium salt of the polymer was then dissolved in water andadded with Amberlyst 15, a protonic acid exchange resin which had beenwashed thoroughly with water until there was no color in the water. Themixture was stirred and filtered. Filtrate was added with freshAmberlyst 15 resin and filtered again. The step was repeated two moretimes. Water was then removed from the final filtrates and the solidswere then dried in a vacuum oven.

Films made from E-PSEPVE acid are wettable by organic solvents.Phenylhexane will have a contact angle less than 40° on the films.

Example 5

This example illustrates the effect of the addition of Poly(NBD/PSEPVE)to a semiconductive oxide dispersion on its work-function.

In this example, Celnax CX-Z300H was also used to determine effect ofpoly(NBD/PSEPVE) on work-function of zinc/antimoney double oxide.Synthesis of of Poly(NBD/PSEPVE) was described later in this example.The procedure described in Example 2 for film preparation of a mixtureof zinc/antimony oxide and Poly(NBD/PSEPVE), and contact potentialdifference measurement for determination of work-function was closelyfollowed. The work-function data listed in Table 3 clearly shows thataddition of Poly(NBD/PSEPVE) to CX-Z300H has enhanced work-function ofantimony/zinc double oxide. High work-function is critical for OLEDs asa buffer layer for device function.

Poly(NBD/PSEPVE) used for adding to Celnax CX-Z300H was made as follows.

a) Synthesis of 3,3,4-trifluoro-4-(perfluorosulfonylethoxy)tricyclo[4.2.1.0^(2,5)]-non-7-ene (NBD-PSEVE):

A 1000 mL Hastelloy C276 reaction vessel was charged with a mixture of2,5-norbornadiene (98%, Aldrich, 100 g), and hydroquinone (0.5 g). Thevessel was cooled to −6° C., evacuated to −20 PSIG, and purged withnitrogen. The pressure was again reduced to −20 PSIG and2-(1,2,2-trifluorovinyloxy)-1,1,2,2-tetrafluoroethanesulfonyl fluoride(305 g) was added. The vessel was agitated and heated to 190° C. atwhich time the inside pressure was 126 PSIG. The reaction temperaturewas maintained at 190° C. for 6 h. The pressure dropped to 47 PSIG atwhich point the vessel was vented and cooled to 25° C.

The crude monomer was distilled using a spinning-band column(BP=110-120° C. @ 40 Torr, 2100 RPM) to afford 361 g of colorless liquidconsisting of a mixture of isomers. The chemical structure was confirmedby both GCMS and ¹⁹F and ¹H NMR. MS: m/e 372 (M⁺), 353 (base, M⁺-F), 289(M⁺-SO₂F), 173 (C₉H₈F₃ ⁺).

b) Synthesis of a TFE and NBD-PSEVE sulfonyl fluoride copolymer:

A 400 mL pressure vessel was swept with nitrogen and charged with 74.4 g(0.20 mol) of NBD-PSEVE, 50 mL of Solkane 365 mfc(1,1,1,3,3-pentafluorobutane) and 0.80 g of Perkadox® 16N. The vesselwas closed, cooled in dry ice, evacuated, and charged with 30 g (0.30mol) of TFE. The vessel contents were heated to 50° C. and agitated for18 hr as the internal pressure decreased from 194 psi to 164 psi. Thevessel was cooled to room temperature and vented to one atmosphere. Thevessel contents were added slowly to excess hexane. The solid wasfiltered, washed with hexane and dried in a vacuum oven at about 80° C.There was isolated 32.3 g of the white copolymer. Its fluorine NMRspectrum showed peaks at +44.7 (1F, SO₂F), −74 to −87 (2F, OCF₂), −95 to−125 (CF₂, 4F from NBD-PSEVE and 4F from TFE), −132.1 (1F, CF). Fromintegration of the NMR, polymer composition was calculated to be 48% TFEand 52% NBD-PSEVE. GPC analysis: Mn=9500, Mw=17300, Mw/Mn=1.82. DSC: Tgat 207° C. Anal. Found: C, 33.83; H, 1.84; F, 45.57.

c) Hydrolysis of a TFE/NBD-PSEVE Sulfonyl Fluoride Copolymer forConversion to Acid Copolymer:

22.53 g (48.5 mmoles —SO₂F) TFE/NBD-PSEVE were placed in a 1000 mLdistillation flask. This flask was equipped with a magnetic stirrer,condenser and nitrogen inlet adapter. To the flask, 350 mLmethanol/water mixture (1:1 v/v) and 19.24 g (200 mmoles) ammoniumcarbonate were added. The flask was then immersed in an oil bath heatedto 75° C. for 24 hours. ¹⁹F-NMR shows the absence of ˜δ40, indicatingthat the sulfonyl fluoride was hydrolyzed to below the detection limit.

The entire content (˜376 g) of the hydrolyzed mixture was furthertreated for conversion to acid. 30 g protonic exchange resins were addedto the mixture and left stirred for 1 hr. The resin was filtered andfresh 30 g acidic resins were added and left stirred for 15 hrs andfiltered again. The filtrate was treated with fresh 20 g acidic resinsfor half an hour and again the filtrate was treated with fresh 30 gacidic resins for half an hour. The final filtrate was then placed inaround bottom flask which was immersed in an oil bath heated to 60° C.Once two thirds of the content were removed through evaporation, the oilbath heat was turned off until the content became dried. Dried solid,which was yellowish, weighed 18.5 g.

A few pieces of the solid was dissolved in water which turned intoacidic. A couple of drops of the solution were cast on a microscopeslide. It formed a smooth continuous film. The film surface can bewetted easily with p-xylene, which is a common solvent for lightemitting materials. TABLE 3 Effect of acid (5 × 10⁻⁴ acid equivalent/1gram-oxide on work-function CPD vs. Kelvin Work-function (eV; Acid ProbeTip ref. To Au) None (Zinc 0.87 4.91 antimonate) Poly(E/PSEPVE) 1.515.64 Poly(NBD/TFE- 1.42 5.54 PSEPVE)

Example 6

This example illustrates the effect of the addition of Nafion® dispersedin methanol to a semiconducive oxide dispersion on its work-function.Nafion® is a trademark for poly(perfluoroethylenesulfonic acid) fromE.I. du Pont de Nemours and Company (Wilmington, Del., USA).

In this example, Celnax CX-Z641 M used for illustration was alsopurchased from Nissan Chemical Industries, LTD from Houston, Tex. TheCelnax is antimony double oxide methanosol, which was determined tocontain 61.4% (w/w) oxide and the rest is methanol. It has pH 8.2 andparticle size of 20 nm by BET method. To determine work-function of thesemiconductive oxide film, a diluted CX-Z641 M was made by mixing14.1889 g of the methanosol with 70.2178 g methanol. The diluted samplecontains only 10.03% (w/w) oxide. It was filtered through a 0.45 μm HVfilter for spin-coating at a speed of 3,000 rpm for 60 seconds on one ofthe ITO substrates described in the general procedure of film samplepreparation. The zinc/antimony double oxide film on the ITO/glasssubstrate was then baked at 110° C. for 10 minutes and the thickness ofthe film was determined to be 100 nm (nanometer). Prior to Kelvin probemeasurement of the oxide film sample, a gold film was measured first.Contact potential difference (CPD) between gold film and the Kelvinprobe tip is 0.615 volt. Contact potential difference between the oxidefilm and Kelvin probe tip was determined to be 0.549 volt. Work-functionof the antimony oxide surface was therefore calculated to be 4.63 eVusing 4.7 eV for work-function of air-aged gold. This work-function datais listed in Table 4 as a control to determine effect of addition ofNafion® on its work-function.

Nafion®/methanol dispersion used for adding to CX-Z641 M was made asfollow. An aqueous Nafion® dispersion having EW of 1000 was made firstusing a procedure similar to the procedure in U.S. Pat. No. 6,150,426,Example 1, Part 2, except that the temperature is approximately 270° C.As made aqueous Nafion® dispersion was then freeze-dried to Nafion®solids. 10.5475 g of the freeze-dried Nafion® solids were mixed with94.2821 g methanol to obtain 10.06% (w/w) Nafion® in methanol. 11.75 gof the methanol-diluted CX-Z641 M dispersion was mixed with 11.68 g ofthe 10.06% Nafion®/methanol dispersion. The resulting dispersioncontains 10.04% (w/w) zinc-antimony oxide/Nafion® in Methanol and has apH of 0.5. Portion of the dispersion was filtered through a 0.45 μm HVfilter for spin-coating at a speed of 5,000 rpm for 60 seconds on one ofthe ITO substrates described in the general procedure of film samplepreparation. The zinc/antimony double oxide film on the ITO/glasssubstrate was then baked at 110° C. in air for 10 minutes and the filmthickness was determined to be 173 nm. Its work-function is listed inTable 4, which shows that Nafion® has enhanced antimony/zinc doubleoxide from 4.63 eV to 5.37 eV. High work-function is critical for OLEDsas a buffer layer for device function.

A portion of the Nafion®/zinc-antimony oxide/methanol dispersion wasadjusted to pH 7.8 with aqueous NH4OH. The dispersion maintains itsstability and baked film made from it still has work-function of 5.38eV. TABLE 4 Effect of Nafion ® on work-function of zinc/antimony doubleoxide CPD vs. Kelvin Work-function (eV; Acid Probe Tip ref. To Au) None(Zinc 0.549 4.63 antimonate) Nafion ® added 1.282 5.37 (pH0.4dispersion) Nafion ® added first, 1.293 5.38 NH4OH second (pH 7.8dispersion)

Comparative Example A

This example illustrates device performance of a polymeric lightemitting diode on an antimony/zinc double oxide film without containingNafion®.

The 10.03% (w/w) antimony/zinc double oxide in methanol producedsemiconductive oxide films, which had work-function of 4.63 eV asillustrated in Example 6. The work-function is low and this comparativeexample is to demonstrate its device function as a buffer layer for alight emitting diode. The 10.03% (w/w) antimony/zinc double oxide inmethanol prepared in Example 6 was filtered through 0.45 μm HV filterfor spin-coating at a speed of 3,000 rpm for 60 seconds on glass/ITObacklight substrates (30 mm×30 mm) and baked at 130° C. in air for 15minutes. Each ITO substrate having ITO thickness of 100 to 150 nmconsists of 3 pieces of 5 mm×5 mm pixels and 1 piece of 2 mm×2 mm pixelfor light emission. The baked zinc/antimony oxide films had thickness of100 nm. The ITO/glass substrates containing the double oxide film weretransferred into a glove box and 76 nm of Lumation Green K2 1303 [1%(w/v) in p-Xylene spun at 1,000 RPM] from Sumitomo Chemicals Company(Japan) were spun on top. The Green K2 layer was baked at 130° C. on ahot plate inside the glove box for 30 minutes before transfer into anevaporator and evaporation of 3 nm of Barium and 250 nm of Aluminum ascathode. Encapsulation was done by epoxy and a glass coverslip. Thedevice had current efficiency less than 0.7 cd/A from above zero to3,000 nits.

Example 7

This example illustrates the effect of the addition of Nafion® dispersedin methanol on the performance of a semiconductive oxide dispersion of apolymeric light emitting diode.

10.04% (w/w) zinc-antimony oxide/Nafion® in methanol producedsemiconductive oxide films which had work-function of 5.37 eV. Thework-function is much higher than that in comparative Example 1, whereNafion® was absent from the double oxide dispersion. This exampledemonstrates the films' device function as a buffer layer for a lightemitting diode. The 10.04% (w/w) zinc-antimony oxide/Nafion® in methanolprepared in Example 6 was filtered through 0.45 μm HV filter forspin-coating at a speed of 5,000 rpm for 60 seconds on glass/ITObacklight substrates (30 mm×30 mm) and baked at 130° C. in air for 15minutes. The remaining fabrication of the devices was carried out in thesame manner as described in Comparative Example 1. The device hadcurrent efficiency 11 cd/A from above zero to 10,000 nits. This exampleclearly shows that addition of Nafion® to antimony-zinc oxide dispersionin methanol has enhanced their work-function and light emitting deviceperformance as a buffer layer.

Comparative Example B

This comparative example illustrates device performance of a polymericlight diode on an antimony/zinc double oxide film without Nafion®.

In this comparative example, 5.99% antimony/zinc oxide dispersion inwater was made by adding 19.3706 g deionized water to 5.5143 g CX-Z300H.The resulting dispersion has a pH of 8. The 5.99% (w/w) antimony/zincdouble oxide in water was first determined to produce films which hadwork-function of 4.44 eV. The work-function is low and this comparativeexample demonstrates the device function as a buffer layer for a lightemitting diode. The 5.99% antimony/zinc double oxide in water was alsofiltered through 0.45 μm HV filter for spin-coating at a speed of 3,000rpm for 60 seconds on glass/ITO backlight substrates (30 mm×30 mm) andbaked at 130° C. in air for 15 minutes. Each ITO substrate having ITOthickness of 100 to 150 nm consists of 3 pieces of 5 mm×5 mm pixels and1 piece of 2 mm×2 mm pixel for light emission. The baked zinc/antimonyoxide films had thickness of 35 nm. The ITO/glass substrates containingthe double oxide film were transferred into a glovebox and 76 nm ofLumation Green K2 1303 [1% (w/v) in p-Xylene spun at 1,000 RPM] fromSumitomo Chemicals Company (Japan) were spun on top. The Green K2 layerswere baked at 130° C. on a hot plate inside the glove box for 30 minutesbefore transfer into an evaporator and evaporation of 3 nm of Barium and250 nm of Aluminum as cathode. Encapsulation was done by epoxy and athin piece of glass lid. The device has current efficieny less than 0.5cd/A from above zero to 3,000 nits. The device efficiency is too low tobe useful.

Example 8

This example illustrates the effect of the addition of Nafion® dispersedin water on the performance of a semiconductive oxide dispersion of apolymeric light diode.

In this example, 7.2% antimony/zinc oxide/Nafion® dispersion in waterwas made by first adding 17.6348 g deionized water to 5.6559 g CX-Z300H.To the resulting dispersion was added 5.6559 g Nafion® (12%, w/w)dispersion described in Example 2. The resulting dispersion had a pH of2.2. The 7.2% (w/w) antimony-zinc oxide/Nafion® in water was firstdetermined to produce semiconductive films which had work-function of5.23 eV. This work-function is much higher than that of the filmsproduced from the composition without Nafion® in Comparative Example 2.This example demonstrates the device function as a buffer layer for alight emitting diode. The 7.2% antimony/zinc oxide/Nafion® dispersionwas filtered through 0.45 μm HV filter for spin-coating at a speed of1,800 rpm for 60 seconds on glass/ITO backlight substrates (30 mm×30 mm)and baked at 130° C. in air for 15 minutes. The baked zinc-antimonyoxide/Nafion® films had thickness of 35 nm. The remaining fabrication ofthe devices was carried out in the same manner as described inComparative Example 2. The device had current efficiency 11 cd/A fromabove zero to 10,000 nits. This example clearly shows that addition ofNafion® to antimony-zinc oxide dispersion in methanol enhanced itswork-function and light emitting device performance as a buffer layer.

Note that not all of the activities described above in the generaldescription or the examples are required, that a portion of a specificactivity may not be required, and that one or more further activitiesmay be performed in addition to those described. Still further, theorder in which activities are listed are not necessarily the order inwhich they are performed.

In the foregoing specification, the concepts have been described withreference to specific embodiments. However, one of ordinary skill in theart appreciates that various modifications and changes can be madewithout departing from the scope of the invention as set forth in theclaims below. Accordingly, the specification and figures are to beregarded in an illustrative rather than a restrictive sense, and allsuch modifications are intended to be included within the scope ofinvention.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims.

It is to be appreciated that certain features are, for clarity,described herein in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, references to values stated in ranges include each and everyvalue within that range subcombination.

1. A buffer composition comprising semiconductive oxide particles and atleast one of (a) a fluorinated acid polymer and (b) a semiconductivepolymer doped with a fluorinated acid polymer.
 2. A buffer compositionof claim 1 wherein the semiconductive oxide particles comprise an oxideof an element selected from group 2 through group 12 elements, andmixtures thereof.
 3. A buffer composition of claim 1 wherein thesemiconductive oxide particles comprise a bimetallic oxide.
 4. A buffercomposition of claim 1 wherein each semiconductive polymer comprises oneor more independently substituted or unsubstituted monomers selectedfrom thiophenes, pyrroles, anilines, fused polycyclic heteroaromatics,and polycyclic heteroaromatics.
 5. A buffer composition of claim 4wherein the thiophenes have structure represented by formulas selectedfrom Formula I and Formula Ia:

wherein: R¹ is independently selected so as to be the same or differentat each occurrence and is selected from hydrogen, alkyl, alkenyl,alkoxy, alkanoyl, alkythio, aryloxy, alkylthioalkyl, alkylaryl,arylalkyl, amino, alkylamino, dialkylamino, aryl, alkylsulfinyl,alkoxyalkyl, alkylsulfonyl, arylthio, arylsulfinyl, alkoxycarbonyl,arylsulfonyl, acrylic acid, phosphoric acid, phosphonic acid, halogen,nitro, cyano, hydroxyl, epoxy, silane, siloxane, alcohol, benzyl,carboxylate, ether, ether carboxylate, amidosulfonate, ether sulfonate,ester sulfonate, and urethane; or both R¹ groups together may form analkylene or alkenylene chain completing a 3, 4, 5, 6, or 7-memberedaromatic or alicyclic ring, which ring may optionally include one ormore divalent nitrogen, sulfur or oxygen atoms; and

wherein: R⁷ is the same or different at each occurrence and is selectedfrom hydrogen, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alcohol,amidosulfonate, benzyl, carboxylate, ether, ether carboxylate, ethersulfonate, ester sulfonate, and urethane, with the proviso that at leastone R⁷ is not hydrogen, and m is 2 or
 3. 6. A buffer composition ofclaim 4 wherein the pyrroles have structure represented by Formula II:

wherein: R¹ is independently selected so as to be the same or differentat each occurrence and is selected from hydrogen, alkyl, alkenyl,alkoxy, alkanoyl, alkythio, aryloxy, alkylthioalkyl, alkylaryl,arylalkyl, amino, alkylamino, dialkylamino, aryl, alkylsulfinyl,alkoxyalkyl, alkylsulfonyl, arylthio, arylsulfinyl, alkoxycarbonyl,arylsulfonyl, acrylic acid, phosphoric acid, phosphonic acid, halogen,nitro, cyano, hydroxyl, epoxy, silane, siloxane, alcohol, benzyl,carboxylate, ether, amidosulfonate, ether carboxylate, ether sulfonate,ester sulfonate, and urethane; or both R¹ groups together may form analkylene or alkenylene chain completing a 3, 4, 5, 6, or 7-memberedaromatic or alicyclic ring, which ring may optionally include one ormore divalent nitrogen, sulfur or oxygen atoms; and R² is independentlyselected so as to be the same or different at each occurrence and isselected from hydrogen, alkyl, alkenyl, aryl, alkanoyl, alkylthioalkyl,alkylaryl, arylalkyl, amino, epoxy, silane, siloxane, alcohol, benzyl,carboxylate, ether, ether carboxylate, ether sulfonate, ester sulfonate,and urethane.
 7. A buffer composition of claim 4 wherein the anilineshave structure represented by formulas selected from Formula III,Formula IVa, and Formula IVb:

wherein: a is 0 or an integer from 1 to 4; b is an integer from 1 to 5,with the proviso that a+b=5; and R¹ is independently selected so as tobe the same or different at each occurrence and is selected fromhydrogen, alkyl, alkenyl, alkoxy, alkanoyl, alkythio, aryloxy,alkylthioalkyl, alkylaryl, arylalkyl, amino, alkylamino, dialkylamino,aryl, alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio, arylsulfinyl,alkoxycarbonyl, arylsulfonyl, acrylic acid, phosphoric acid, phosphonicacid, halogen, nitro, cyano, hydroxyl, epoxy, silane, siloxane, alcohol,benzyl, carboxylate, ether, ether carboxylate, amidosulfonate, ethersulfonate, ester sulfonate, and urethane; or both R¹ groups together mayform an alkylene or alkenylene chain completing a 3, 4, 5, 6, or7-membered aromatic or alicyclic ring, which ring may optionally includeone or more divalent nitrogen, sulfur or oxygen atoms;

where a, b and R¹ are as defined above.
 8. A buffer composition of claim4 wherein the fused polycyclic heteroaromatics have structurerepresented by formulas selected from Formula V, and Formulas Va-Vg:

wherein: Q is S or NR⁶; R⁶ is hydrogen or alkyl; R⁸, R⁹, R¹⁰, and R¹¹are independently selected so as to be the same or different at eachoccurrence and are selected from hydrogen, alkyl, alkenyl, alkoxy,alkanoyl, alkythio, aryloxy, alkylthioalkyl, alkylaryl, arylalkyl,amino, alkylamino, dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl,alkylsulfonyl, arylthio, arylsulfinyl, alkoxycarbonyl, arylsulfonyl,acrylic acid, phosphoric acid, phosphonic acid, halogen, nitro, nitrile,cyano, hydroxyl, epoxy, silane, siloxane, alcohol, benzyl, carboxylate,ether, ether carboxylate, amidosulfonate, ether sulfonate, estersulfonate, and urethane; and at least one of R⁸ and R⁹, R⁹ and R¹⁰, andR¹⁰ and R¹¹ together form an alkenylene chain completing a 5 or6-membered aromatic ring, which ring may optionally include one or moredivalent nitrogen, sulfur or oxygen atoms; and

wherein: Q is S or NH; and T is the same or different at each occurrenceand is selected from S, NR⁶, O, SiR⁶ ₂, Se, and PR⁶; R⁶ is hydrogen oralkyl.
 9. A buffer composition of claim 4 wherein the polycyclicheteroaromatics have structure represented by Formula VI:

wherein: Q is S or NR⁶; T is selected from S, NR⁶, O, SiR⁶ ₂, Se, andPR⁶; E is selected from alkenylene, arylene, and heteroarylene; R⁶ ishydrogen or alkyl; R¹² is the same or different at each occurrence andis selected from hydrogen, alkyl, alkenyl, alkoxy, alkanoyl, alkythio,aryloxy, alkylthioalkyl, alkylaryl, arylalkyl, amino, alkylamino,dialkylamino, aryl, alkylsulfinyl, alkoxyalkyl, alkylsulfonyl, arylthio,arylsulfinyl, alkoxycarbonyl, arylsulfonyl, acrylic acid, phosphoricacid, phosphonic acid, halogen, nitro, nitrile, cyano, hydroxyl, epoxy,silane, siloxane, alcohol, benzyl, carboxylate, ether, ethercarboxylate, amidosulfonate, ether sulfonate, ester sulfonate, andurethane; or two R¹² groups together may form an alkylene or alkenylenechain completing a 3, 4, 5, 6, or 7-membered aromatic or alicyclic ring,which ring may optionally include one or more divalent nitrogen, sulfuror oxygen atoms.
 10. A buffer composition of claim 3 wherein thesemiconductive oxide particles are selected from indium-tin oxide(“ITO”), indium-zinc oxide (“IZO”), gallium-indium oxide, andzinc-antimony double oxide.
 11. A buffer composition of claim 1 whereinthe oxide particles comprise an oxide of two elements selected fromgroup 2 through group 16, and mixtures thereof.
 12. A buffer compositionof claim 11 wherein the oxide particles are selected from indium-tinoxide (“ITO”), indium-zinc oxide (“IZO”), gallium-indium oxide, andzinc-antimony double oxide.
 13. A buffer composition of claim 1 whereinthe oxide particles are selected from antimony doped oxide andzirconium.
 14. A buffer composition of claim 1 wherein the fluorinatedacid polymer (“FAP”) is highly fluorinated.
 15. A buffer composition ofclaim 1 wherein the FAP is wettable.
 16. A buffer composition of claim 1wherein the FAP is non-wettable.
 17. A buffer composition of claim 1wherein the FAP is an FSA polymer.
 18. A buffer composition of claim 1wherein the FAP is colloid-forming.
 19. A buffer composition of claim 18wherein the FAP is wettable.
 20. A buffer composition of claim 18wherein the FAP is non-wettable.
 21. A buffer composition of claim 19wherein the FAP is an FSA polymer.
 22. A buffer composition of claim 18wherein the FAP is a polymeric sulfonic acid.
 23. A buffer compositionof claim 19 wherein the FAP is doped into a semiconductive polymer andthe acid-doped semiconductive polymer forms a film.
 24. A buffercomposition of claim 20 wherein the FAP is doped into a semiconductivepolymer and the acid-doped semiconductive polymer forms a film.
 25. Abuffer composition of claim 1 wherein the polymeric acid has a formulaselected from Formulas VII, VIII, IX, XII, and XV.
 26. A buffercomposition of claim 25 wherein the polymeric acid has a siloxanependant group.
 27. A buffer composition of claim 25 wherein thepolymeric acid has a pendant group having a formula selected fromFormula X and Formula XIV.
 28. A buffer composition of claim 1 whereinthe semiconductive polymer comprises at least one first precursormonomer and at least one second precursor monomer.
 29. A buffercomposition of claim 28 wherein at least one second precursor monomer isnon-conductive.
 30. A buffer composition of claim 1 wherein an aqueousdisperson of the semiconductive polymer doped with a fluorinated acidpolyer has a pH in the range of from about 1.5 to about
 4. 31. Anelectronic device comprising a buffer composition of claim 1.